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Multiple security vulnerabilities have been identified and addressed in grpc-go affecting the xDS RBAC authorization engine (internal/xds/rbac) and the HTTP/2 transport server implementation (internal/transport). These vulnerabilities could result in:
Authorization Bypass (Fail-Open) when translating xDS RBAC policies containing Metadata or RequestedServerName fields.
Denial of Service (High CPU Consumption) due to an HTTP/2 Rapid Reset mitigation bypass during client-initiated stream resets.
Denial of Service (Server Panic) when parsing crafted xDS RBAC policies containing NOT rules around unsupported fields.
Impact
What kind of vulnerability is it? Who is impacted?
xDS RBAC Authorization Bypass via Metadata & RequestedServerName matchers
Affected Component: xDS RBAC
Impact: When building policy matchers for gRPC RBAC from xDS configurations, unsupported permission and principal rules (specifically Metadata and RequestedServerName) were silently ignored and treated as no-ops.
If an authorization policy relied purely on these matchers for access control, treating those rules as no-ops effectively removed the restrictions.
If these unsupported rules were nested inside logical NOT rules (Permission_NotRule / Principal_NotId) or multi-condition OR/AND rules, silently dropping them changed the boolean logic flow of the authorization engine.
As a result, policy evaluation decisions could fail open, allowing unauthorized clients to access protected gRPC services or resources.
HTTP/2 Rapid Reset Mitigation Bypass / Denial of Service via Stream Aborts
Affected Component: HTTP/2 transport
Impact: Earlier mitigations in grpc-go for HTTP/2 Rapid Reset only applied threshold checks to items that directly resulted in control frames being written back to the wire, such as SETTINGS ACKs or server-initiated RST_STREAMs.
When a client initiated a rapid flood of stream creation (HEADERS) immediately followed by stream termination RST_STREAM, items queued up in the control buffer without counting against the transport response frame threshold. An attacker can repeatedly trigger this flood sequence to bypass reader blocking, resulting in high CPU usage, and Denial of Service (DoS).
Denial of Service (Panic) in xDS RBAC Engine via Unsupported Fields inside NOT Rules
Affected Component: xDS RBAC
Impact: The xDS RBAC policy translators recursively generate matchers for nested rules. When a NOT rule wrapped an unsupported or unhandled field (such as SourcedMetadata), the recursive step returned an empty matcher. This could result in a runtime panic when the RBAC engine attempts to authorize an incoming request.
An attacker or misconfigured/malicious xDS management server delivering an LDS/RDS update containing a NOT rule around an unhandled field causes the gRPC server process to crash immediately (CWE-248 / Denial of Service).
Patches
Has the problem been patched? What versions should users upgrade to?
All three issues have been fixed in master and will be released in 1.82.1 shortly.
Workarounds
Is there a way for users to fix or remediate the vulnerability without upgrading?
If upgrading grpc-go immediately is not possible, apply the following workarounds based on your deployment architecture:
For xDS RBAC Vulnerabilities & Panics: Ensure that upstream xDS management servers do not push RBAC policies containing Metadata, RequestedServerName, or NOT rules wrapping unsupported fields (such as SourcedMetadata) to grpc-go servers.
For HTTP/2 Rapid Reset DOS: Configure upstream reverse proxies or load balancers (such as Envoy) with strict HTTP/2 max_concurrent_streams limits and active rate limiting on RST_STREAM frequency per connection.
A vulnerability exists in gRPC-Go servers configured with xds.NewGRPCServer() where a crafted request missing both :authority and Host headers can cause a server panic, resulting in a Denial of Service (DoS).
Servers built with xds.NewGRPCServer install an xDS routing interceptor on every RPC. This interceptor looks up the request’s :authority header to pick a virtual host. The HTTP/2 server transport previously accepted requests that had neither :authority nor Host. When this happened, the xDS routing interceptor attempted to access the first element of an empty slice of authorities, leading to an index out of bounds panic. Since the per-RPC goroutine does not recover from panics, the entire server process would terminate.
This panic occurs in the interceptor pipeline, meaning the transport credentials handshake (TLS, mTLS, or ALTS) and HTTP/2 connection establishment must complete successfully before the crafted request can reach this logic.
Insecure/Standard TLS: If the server permits insecure (plaintext) connections or standard credentials (where client certs are not checked), any unauthenticated remote attacker can trigger the crash.
mTLS / ALTS: If strict transport-level authentication is enforced at the network edge or transport layer (e.g., requiring a valid client certificate), the attacker must possess valid transport credentials to initiate the stream and trigger the panic.
Impact
An attacker can cause a complete outage of the gRPC server by sending a request missing both :authority and Host headers, provided they can successfully establish a transport connection.
Patches
The issue has been addressed in master (and backported to 1.83.2 and 1.82.2). The fix updates the HTTP/2 transport layer to reject requests missing both :authority and Host headers early, maintaining consistency with and other gRPC language implementations.
In google.golang.org/grpc, servers configured with xDS routing can panic when processing requests that lack both :authority and Host headers. The HTTP/2 transport layer accepted requests missing these headers, and the xDS server routing interceptor attempted to index the empty authority slice, causing an unhandled panic and terminating the server.
A vulnerability in the xDS RBAC HTTP filter implementation in grpc-go allows remote attackers to bypass authorization policies (specifically DENY rules) by using mixed-case or canonical-case header matchers (e.g., X-Role instead of x-role). Additionally, the safety guards introduced by gRFC A41 to block grpc- prefixed headers can be evaded via variations in casing (e.g., Grpc-Status).
Impact
When an operator defines an RBAC policy referencing headers containing uppercase letters (e.g. X-Role), grpc-go fails to match incoming metadata keys because they are unconditionally lowercased. Because of this case-sensitivity mismatch, a policy designed to block requests containing specific header values fails open: the rule is evaluated as a non-match, and traffic that should have been rejected is served.
Furthermore, gRFC A41 requires rejecting configuration schemas specifying header matchers starting with grpc-. Because this check is executed case-sensitively in grpc-go, attackers can bypass the validation by specifying titles like Grpc-Status.
Patches
The problem is fixed in master and in the 1.83.1 release.
An unauthenticated remote attacker can initiate a gRPC stream and purposefully fragment their payload into millions of tiny (e.g., 1-byte) HTTP/2 DATA frames. Even if the total payload volume falls within the configured connection and stream flow-control windows, each independent fragment incurs memory overhead due to internal tracking structures and queue allocation.
Repeated fragmentation massively inflates the heap space consumed by the stream. An attacker multiplexing multiple concurrent streams can exhaust the memory bounds of the runtime, forcing a runtime panic or OutOfMemory condition and leading to a remote Denial of Service (DoS).
Patches
The change to fix this issue is merged in master and a patch release, 1.83.1, has been published that contains this fix.
Workarounds
This vulnerability is mitigated by implementing receive buffer compaction. Consecutive small data buffers are automatically coalesced into larger buffers from a shared pool once the overhead is perceived to be excessive relative to actual payload data, drastically minimizing per-frame memory overheads.
This behavior is enabled by default. A temporary escape hatch is provided via the environment variable GRPC_GO_EXPERIMENTAL_ENABLE_RECEIVE_BUFFER_COMPACTION=false to disable the feature if unforeseen issues arise, but it will be removed in a future release.
In google.golang.org/grpc, the xDS RBAC HTTP filter does not lowercase header matcher names before evaluating them against incoming request metadata. When an RBAC policy defines rules (such as DENY) referencing headers with uppercase or mixed-case characters, the rule fails to match, causing authorization policies to fail open. Additionally, callers can evade gRFC A41 validation blocking "grpc-" prefixed headers and ":scheme" via variations in casing.
xds/rbac: Fix a bug where nested Principal or Permission rules with :scheme or grpc- prefixed header matchers were not rejected, which could cause DENY rules to fail open. (#9258)
xds/rbac: Fix a bug where a header matcher whose name was not lowercase, such as X-Role, matched no header, which could cause DENY rules to fail open. (#9332)
server: Stop reading from connections when flooded by HTTP/2 frames to mitigate resource exhaustion. The default value for this limit is 100 frames, excluding DATA and HEADERS, and may be changed by setting environment variable GRPC_GO_EXPERIMENTAL_CONTROL_BUFFER_THROTTLE_LIMIT.
xds/rbac: Support Metadata and RequestedServerName permissions matcher fields. If present in a DENY rule, previously these would be ignored and fail-open.
xds/rbac: Fix panic when parsing unsupported fields in NotRule/NotId permissions.
xds/rbac: Support the deprecated source_ip principal identifier by treating it as equivalent to direct_remote_ip.
xds: Fix panic when parsing route header matchers configured with empty exact_match, prefix_match, or suffix_match strings. (#9223)
New Features
xds/googlec2p: Enable DirectPath over Interconnect support for on-premises clients via the force-xds target URI query parameter. (#9133)
xds: Enable xDS configuration to control which fields get propagated from ORCA backend metric reports to LRS load reports. (#9145)
authz: Add OnPolicyUpdate callback to FileWatcherOptions to notify when an authz policy is loaded or updated. (#9142)
xds: Add support for the GCP Authentication HTTP Filter, which automatically fetches and attaches GCP Service Account Identity JWT tokens to outgoing RPCs.
This feature can be enabled by setting environment variable GRPC_EXPERIMENTAL_XDS_GCP_AUTHENTICATION_FILTER=true. (#9119)
xds: Add support for xDS-based HTTP CONNECT proxies.
This feature can be enabled by setting environment variable GRPC_EXPERIMENTAL_XDS_HTTP_CONNECT=true. (#9151)
xds: Add support for contains_match in route header matchers. (#9223)
Bug Fixes
credentials/alts: Fix panic when processing malformed frames by validating that the message frame length exceeds the message type field size. (#9197)
grpc: Fix compilation on Plan 9 targets (GOOS=plan9), broken since v1.81.0. (#9255)
server: Stop reading from the connection when flooded by HTTP/2 frames. The default value for this limit is 100 frames, excluding DATA and HEADERS, and may be changed by setting environment variable GRPC_GO_EXPERIMENTAL_CONTROL_BUFFER_THROTTLE_LIMIT.
xds/rbac: Support Metadata and RequestedServerName permissions matcher fields. If present in a DENY rule, previously these would be ignored and fail-open.
xds/rbac: Fix panic when parsing unsupported fields in NotRule/NotId permissions.
xds/rbac: Support the deprecated source_ip principal identifier by treating it as equivalent to direct_remote_ip.
server: Remove support for GRPC_GO_EXPERIMENTAL_DISABLE_STRICT_PATH_CHECKING environment varibale. Strict incoming RPC path validation (which has been the default since v1.79.3) can no longer be disabled. (#9112)
transport: Add environment variable to change the default max header list size from 16MB to 8KB. This may be enabled by setting GRPC_GO_EXPERIMENTAL_ENABLE_8KB_DEFAULT_HEADER_LIST_SIZE=true. This will be enabled by default in a subsequent release. (#9019)
balancer: Load Balancing policy registry is now case-sensitive. Set GRPC_GO_EXPERIMENTAL_CASE_SENSITIVE_BALANCER_REGISTRIES=false (and file an issue) to revert to case-insensitive behavior. (#9017)
New Features
experimental/stats: Expose a new API, NewContextWithLabelCallback, to register a callback that is invoked when telemetry labels are added. (#8877)
client: Return a portion of the response body in the error message, when the client receives an unexpected non-gRPC HTTP response, to make debugging easier. (#8929)
server: Add environment variable GRPC_GO_SERVER_GOROUTINE_LABELS that controls setting runtime/pprof.Labels on goroutines spawned by the server. Set GRPC_GO_SERVER_GOROUTINE_LABELS=grpc.method=true to add the grpc.method label on goroutines spawned to handle incoming requests. (#9082)
xds/server: Fix a memory leak of HTTP filter instances occurring when route configurations are updated in-place during a Route Discovery Service (RDS) update. (#9138)
grpc: In the deprecated gzip Compressor (used via the deprecated WithCompressor dial option), enforce the MaxRecvMsgSize limit on the decompressed message buffer, preventing excessive memory allocation from highly compressed payloads. (#9114)
stats/opentelemetry: Record retry attempts, grpc.previous-rpc-attempts, at the call level and not the attempt level. (#8923)
encoding: Ensure Close() is always called on readers returned from Compressor.Decompress if possible. (#9135)
channelz: Fix the LastMessageSentTimestamp and LastMessageReceivedTimestamp fields in SocketMetrics to ensure they contain correct timestamp values. (#9109)
xds/rbac: Fix a potential authorization bypass caused by incorrectly falling through URI/DNS SANs to Subject Distinguished Name (DN) when matching the authenticated principal name. With this fix, only the first non-empty identity source will be used, as per gRFC A41. (#9111)
balancer/rls: Switch gauge metrics to asynchronous emission (once per collection cycle) to reduce telemetry noise and align with other gRPC language implementations. (#8808)
Dependencies
Minimum supported Go version is now 1.25. (#8969)
Bug Fixes
xds: Use the leaf cluster's security config for the TLS handshake instead of the aggregate cluster's config. (#8956)
transport: Send a RST_STREAM when receiving an END_STREAM when the stream is not already half-closed. (#8832)
xds: Fix ADS resource name validation to prevent a panic. (#8970)
New Features
grpc/stats: Add support for custom labels in per-call metrics (gRFC A108). (#9008)
xds: Add support for Server Name Indication (SNI) and SAN validation (gRFC A101). Disabled by default. To enable, set GRPC_EXPERIMENTAL_XDS_SNI=true environment variable. (#9016)
xds: Add support to control which fields get propagated from ORCA backend metric reports to LRS load reports (gRFC A85). Disabled by default. To enable, set GRPC_EXPERIMENTAL_XDS_ORCA_LRS_PROPAGATION=true. (#9005)
xds: Add metrics to track xDS client connectivity and cached resource state (gRFC A78). (#8807)
stats/otel: Enhance grpc.subchannel.disconnections metric by adding disconnection reason to the grpc.disconnect_error label (gRFC A94). This provides granular insights into why subchannels are closing. (#8973)
mem: Add mem.Buffer.Slice() API to slice the buffer like a slice. (#8977)
alts: Pool read buffers to lower memory utilization when sockets are unreadable. (#8964)
transport: Pool HTTP/2 framer read buffers to reduce idle memory consumption. Currently limited to Linux for ALTS and non-encrypted transports (TCP, Unix). To disable, set GRPC_GO_EXPERIMENTAL_HTTP_FRAMER_READ_BUFFER_POOLING=false and report any issues. (#9032)
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This PR contains the following updates:
v1.79.3→v1.83.1gRPC-Go: xDS RBAC and HTTP/2 Vulnerabilities
GHSA-hrxh-6v49-42gf / GO-2026-6061
More information
Details
Multiple security vulnerabilities have been identified and addressed in grpc-go affecting the xDS RBAC authorization engine (internal/xds/rbac) and the HTTP/2 transport server implementation (internal/transport). These vulnerabilities could result in:
MetadataorRequestedServerNamefields.NOTrules around unsupported fields.Impact
What kind of vulnerability is it? Who is impacted?
xDS RBAC Authorization Bypass via
Metadata&RequestedServerNamematcherspermissionandprincipalrules (specificallyMetadataandRequestedServerName) were silently ignored and treated as no-ops.NOTrules (Permission_NotRule/Principal_NotId) or multi-conditionOR/ANDrules, silently dropping them changed the boolean logic flow of the authorization engine.As a result, policy evaluation decisions could fail open, allowing unauthorized clients to access protected gRPC services or resources.
HTTP/2 Rapid Reset Mitigation Bypass / Denial of Service via Stream Aborts
SETTINGSACKs or server-initiatedRST_STREAMs.When a client initiated a rapid flood of stream creation (
HEADERS) immediately followed by stream terminationRST_STREAM, items queued up in the control buffer without counting against the transport response frame threshold. An attacker can repeatedly trigger this flood sequence to bypass reader blocking, resulting in high CPU usage, and Denial of Service (DoS).Denial of Service (Panic) in xDS RBAC Engine via Unsupported Fields inside NOT Rules
NOTrule wrapped an unsupported or unhandled field (such asSourcedMetadata), the recursive step returned an empty matcher. This could result in a runtime panic when the RBAC engine attempts to authorize an incoming request.An attacker or misconfigured/malicious xDS management server delivering an LDS/RDS update containing a
NOTrule around an unhandled field causes the gRPC server process to crash immediately (CWE-248 / Denial of Service).Patches
Has the problem been patched? What versions should users upgrade to?
All three issues have been fixed in
masterand will be released in 1.82.1 shortly.Workarounds
Is there a way for users to fix or remediate the vulnerability without upgrading?
If upgrading grpc-go immediately is not possible, apply the following workarounds based on your deployment architecture:
Metadata,RequestedServerName, orNOTrules wrapping unsupported fields (such asSourcedMetadata) to grpc-go servers.max_concurrent_streamslimits and active rate limiting onRST_STREAMfrequency per connection.Severity
8.27.55.9Severity
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:NReferences
This data is provided by OSV and the GitHub Advisory Database (CC-BY 4.0).
Vulnerabilities in the xDS RBAC authorization engine and the HTTP/2 transport server implementation in google.golang.org/grpc
GHSA-hrxh-6v49-42gf / GO-2026-6061
More information
Details
Vulnerabilities in the xDS RBAC authorization engine and the HTTP/2 transport server implementation in google.golang.org/grpc
Severity
Unknown
References
This data is provided by OSV and the Go Vulnerability Database (CC-BY 4.0).
gRPC-Go xDS servers: Denial of Service (DoS) via crash due to missing
:authorityandHostheadersCVE-2026-84445 / GHSA-2v4p-qf9q-27wj / GO-2026-6443
More information
Details
A vulnerability exists in gRPC-Go servers configured with
xds.NewGRPCServer()where a crafted request missing both:authorityandHostheaders can cause a server panic, resulting in a Denial of Service (DoS).Servers built with
xds.NewGRPCServerinstall an xDS routing interceptor on every RPC. This interceptor looks up the request’s:authorityheader to pick a virtual host. The HTTP/2 server transport previously accepted requests that had neither:authoritynorHost. When this happened, the xDS routing interceptor attempted to access the first element of an empty slice of authorities, leading to an index out of bounds panic. Since the per-RPC goroutine does not recover from panics, the entire server process would terminate.This panic occurs in the interceptor pipeline, meaning the transport credentials handshake (TLS, mTLS, or ALTS) and HTTP/2 connection establishment must complete successfully before the crafted request can reach this logic.
Impact
An attacker can cause a complete outage of the gRPC server by sending a request missing both
:authorityandHostheaders, provided they can successfully establish a transport connection.Patches
The issue has been addressed in
master(and backported to1.83.2and1.82.2). The fix updates the HTTP/2 transport layer to reject requests missing both:authorityandHostheaders early, maintaining consistency with and other gRPC language implementations.Severity
High
References
This data is provided by OSV and the GitHub Advisory Database (CC-BY 4.0).
Server panic via missing authority or Host headers in google.golang.org/grpc
CVE-2026-84445 / GHSA-2v4p-qf9q-27wj / GO-2026-6443
More information
Details
In google.golang.org/grpc, servers configured with xDS routing can panic when processing requests that lack both :authority and Host headers. The HTTP/2 transport layer accepted requests missing these headers, and the xDS server routing interceptor attempted to index the empty authority slice, causing an unhandled panic and terminating the server.
Severity
Unknown
References
This data is provided by OSV and the Go Vulnerability Database (CC-BY 4.0).
gRPC-Go: xDS RBAC HTTP Filter bypass via mixed-case Header Matching and gRFC A41 validation evasion
CVE-2026-84303 / GHSA-qc2q-p7wx-3px3 / GO-2026-6441
More information
Details
Summary
A vulnerability in the xDS RBAC HTTP filter implementation in grpc-go allows remote attackers to bypass authorization policies (specifically DENY rules) by using mixed-case or canonical-case header matchers (e.g., X-Role instead of x-role). Additionally, the safety guards introduced by gRFC A41 to block grpc- prefixed headers can be evaded via variations in casing (e.g., Grpc-Status).
Impact
When an operator defines an RBAC policy referencing headers containing uppercase letters (e.g. X-Role), grpc-go fails to match incoming metadata keys because they are unconditionally lowercased. Because of this case-sensitivity mismatch, a policy designed to block requests containing specific header values fails open: the rule is evaluated as a non-match, and traffic that should have been rejected is served.
Furthermore, gRFC A41 requires rejecting configuration schemas specifying header matchers starting with grpc-. Because this check is executed case-sensitively in grpc-go, attackers can bypass the validation by specifying titles like Grpc-Status.
Patches
The problem is fixed in
masterand in the 1.83.1 release.Severity
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:NReferences
This data is provided by OSV and the GitHub Advisory Database (CC-BY 4.0).
gRPC-Go: Heap Memory Exhaustion (OOM) via HTTP/2 DATA Frame Fragmentation
CVE-2026-84304 / GHSA-vp52-pcj8-j9qc / GO-2026-6348
More information
Details
Impact
An unauthenticated remote attacker can initiate a gRPC stream and purposefully fragment their payload into millions of tiny (e.g., 1-byte) HTTP/2 DATA frames. Even if the total payload volume falls within the configured connection and stream flow-control windows, each independent fragment incurs memory overhead due to internal tracking structures and queue allocation.
Repeated fragmentation massively inflates the heap space consumed by the stream. An attacker multiplexing multiple concurrent streams can exhaust the memory bounds of the runtime, forcing a runtime panic or OutOfMemory condition and leading to a remote Denial of Service (DoS).
Patches
The change to fix this issue is merged in
masterand a patch release, 1.83.1, has been published that contains this fix.Workarounds
This vulnerability is mitigated by implementing receive buffer compaction. Consecutive small data buffers are automatically coalesced into larger buffers from a shared pool once the overhead is perceived to be excessive relative to actual payload data, drastically minimizing per-frame memory overheads.
This behavior is enabled by default. A temporary escape hatch is provided via the environment variable
GRPC_GO_EXPERIMENTAL_ENABLE_RECEIVE_BUFFER_COMPACTION=falseto disable the feature if unforeseen issues arise, but it will be removed in a future release.Severity
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NReferences
This data is provided by OSV and the GitHub Advisory Database (CC-BY 4.0).
Heap Memory Exhaustion (OOM) via HTTP/2 DATA Frame Fragmentation in google.golang.org/grpc
CVE-2026-84304 / GHSA-vp52-pcj8-j9qc / GO-2026-6348
More information
Details
Heap Memory Exhaustion (OOM) via HTTP/2 DATA Frame Fragmentation in google.golang.org/grpc
Severity
Unknown
References
This data is provided by OSV and the Go Vulnerability Database (CC-BY 4.0).
Bypass of xDS RBAC HTTP filter header matching in google.golang.org/grpc
CVE-2026-84303 / GHSA-qc2q-p7wx-3px3 / GO-2026-6441
More information
Details
In google.golang.org/grpc, the xDS RBAC HTTP filter does not lowercase header matcher names before evaluating them against incoming request metadata. When an RBAC policy defines rules (such as DENY) referencing headers with uppercase or mixed-case characters, the rule fails to match, causing authorization policies to fail open. Additionally, callers can evade gRFC A41 validation blocking "grpc-" prefixed headers and ":scheme" via variations in casing.
Severity
Unknown
References
This data is provided by OSV and the Go Vulnerability Database (CC-BY 4.0).
Release Notes
grpc/grpc-go (google.golang.org/grpc)
v1.83.1: Release 1.83.1Compare Source
Security
PrincipalorPermissionrules with:schemeorgrpc-prefixed header matchers were not rejected, which could cause DENY rules to fail open. (#9258)hostheader matcher was not being replaced with:authorityin nestedPrincipalorPermissionrules. (#9258)X-Role, matched no header, which could cause DENY rules to fail open. (#9332):schemeorgrpc-prefixed header matcher was accepted when its name was not lowercase. (#9332)Hostheader matcher was not replaced with:authority. (#9332)Performance
v1.83.0: Release 1.83.0Compare Source
Security
GRPC_GO_EXPERIMENTAL_CONTROL_BUFFER_THROTTLE_LIMIT.MetadataandRequestedServerNamepermissions matcher fields. If present in a DENY rule, previously these would be ignored and fail-open.NotRule/NotIdpermissions.source_ipprincipal identifier by treating it as equivalent todirect_remote_ip.exact_match,prefix_match, orsuffix_matchstrings. (#9223)New Features
force-xdstarget URI query parameter. (#9133)OnPolicyUpdatecallback toFileWatcherOptionsto notify when an authz policy is loaded or updated. (#9142)GRPC_EXPERIMENTAL_XDS_GCP_AUTHENTICATION_FILTER=true. (#9119)GRPC_EXPERIMENTAL_XDS_HTTP_CONNECT=true. (#9151)contains_matchin route header matchers. (#9223)Bug Fixes
GOOS=plan9), broken since v1.81.0. (#9255)v1.82.2: Release 1.82.2Compare Source
Security
:authorityandHostheaders with HTTP 400 and statusInternal. (#9365)v1.82.1: Release 1.82.1Compare Source
Security
GRPC_GO_EXPERIMENTAL_CONTROL_BUFFER_THROTTLE_LIMIT.MetadataandRequestedServerNamepermissions matcher fields. If present in a DENY rule, previously these would be ignored and fail-open.NotRule/NotIdpermissions.source_ipprincipal identifier by treating it as equivalent todirect_remote_ip.v1.82.0: Release 1.82.0Compare Source
Behavior Changes
GRPC_GO_EXPERIMENTAL_DISABLE_STRICT_PATH_CHECKINGenvironment varibale. Strict incoming RPC path validation (which has been the default sincev1.79.3) can no longer be disabled. (#9112)16MBto8KB. This may be enabled by settingGRPC_GO_EXPERIMENTAL_ENABLE_8KB_DEFAULT_HEADER_LIST_SIZE=true. This will be enabled by default in a subsequent release. (#9019)GRPC_GO_EXPERIMENTAL_CASE_SENSITIVE_BALANCER_REGISTRIES=false(and file an issue) to revert to case-insensitive behavior. (#9017)New Features
NewContextWithLabelCallback, to register a callback that is invoked when telemetry labels are added. (#8877)GRPC_GO_SERVER_GOROUTINE_LABELSthat controls settingruntime/pprof.Labelson goroutines spawned by the server. SetGRPC_GO_SERVER_GOROUTINE_LABELS=grpc.method=trueto add thegrpc.methodlabel on goroutines spawned to handle incoming requests. (#9082)Bug Fixes
gzipCompressor (used via the deprecatedWithCompressordial option), enforce theMaxRecvMsgSizelimit on the decompressed message buffer, preventing excessive memory allocation from highly compressed payloads. (#9114)grpc.previous-rpc-attempts, at the call level and not the attempt level. (#8923)Close()is always called on readers returned fromCompressor.Decompressif possible. (#9135)LastMessageSentTimestampandLastMessageReceivedTimestampfields inSocketMetricsto ensure they contain correct timestamp values. (#9109)v1.81.1: Release 1.81.1Compare Source
Security
v1.81.0: Release 1.81.0Compare Source
Behavior Changes
Dependencies
Bug Fixes
RST_STREAMwhen receiving anEND_STREAMwhen the stream is not already half-closed. (#8832)New Features
GRPC_EXPERIMENTAL_XDS_SNI=trueenvironment variable. (#9016)GRPC_EXPERIMENTAL_XDS_ORCA_LRS_PROPAGATION=true. (#9005)grpc.subchannel.disconnectionsmetric by adding disconnection reason to thegrpc.disconnect_errorlabel (gRFC A94). This provides granular insights into why subchannels are closing. (#8973)mem.Buffer.Slice()API to slice the buffer like a slice. (#8977)Performance Improvements
GRPC_GO_EXPERIMENTAL_HTTP_FRAMER_READ_BUFFER_POOLING=falseand report any issues. (#9032)v1.80.0Compare Source
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