diff --git a/legacy/phpstan-baseline.neon b/legacy/phpstan-baseline.neon
index 246d95cc6..46e66db0c 100644
--- a/legacy/phpstan-baseline.neon
+++ b/legacy/phpstan-baseline.neon
@@ -7122,12 +7122,6 @@ parameters:
 			count: 1
 			path: src/Service/Shell.php
 
-		-
-			message: '#^Method Platformsh\\Cli\\Service\\Shell\:\:runProcess\(\) should return int but returns int\|null\.$#'
-			identifier: return.type
-			count: 1
-			path: src/Service/Shell.php
-
 		-
 			message: '#^Parameter \#1 \$messages of method Symfony\\Component\\Console\\Output\\OutputInterface\:\:write\(\) expects iterable\|string, string\|null given\.$#'
 			identifier: argument.type
diff --git a/legacy/src/Service/Config.php b/legacy/src/Service/Config.php
index fb33936ba..38b4ed046 100644
--- a/legacy/src/Service/Config.php
+++ b/legacy/src/Service/Config.php
@@ -547,7 +547,7 @@ public function getVersion(): string
             return $this->version;
         }
         $version = $this->getWithDefault('application.version', '@version-placeholder@');
-        if (str_starts_with((string) $version, '@') && str_ends_with((string) $version, '@')) {
+        if (str_starts_with((string) $version, '@') && str_ends_with((string) $version, '@') && !str_starts_with(CLI_ROOT, 'phar://')) {
             // Silently try getting the version from Git.
             $tag = (new Shell())->execute(['git', 'describe', '--tags'], CLI_ROOT);
             if (is_string($tag) && str_starts_with($tag, 'v')) {
diff --git a/legacy/src/Service/Shell.php b/legacy/src/Service/Shell.php
index 69ad5c87c..dc9d0d3d9 100644
--- a/legacy/src/Service/Shell.php
+++ b/legacy/src/Service/Shell.php
@@ -213,9 +213,14 @@ private function runProcess(Process $process, bool $mustRun = false, bool $quiet
                     $output->write(preg_replace('/(^|[\n\r]+)(.)/', '$1  $2', $buffer));
                 }
             });
-        } catch (ProcessFailedException) {
+        } catch (ProcessFailedException $e) {
             if (!$mustRun) {
-                return $process->getExitCode();
+                // The exit code is null if the process failed to start.
+                return $process->getExitCode() ?? 1;
+            }
+            // A process that failed to start has no output to report.
+            if (!$process->isStarted()) {
+                throw $e;
             }
             // The default for Symfony's ProcessFailedException is to print the
             // entire STDOUT and STDERR. But if $quiet is disabled, then the user
@@ -278,6 +283,10 @@ protected function findWhere(string $command, bool $noticeOnError = true): strin
     public function exceptionMeansCommandDoesNotExist(ProcessFailedException $e): bool
     {
         $process = $e->getProcess();
+        // A process that failed to start has no exit code or output to check.
+        if (!$process->isStarted()) {
+            return false;
+        }
         if ($process->getExitCode() === 127) {
             return true;
         }
diff --git a/legacy/tests/Service/ShellServiceTest.php b/legacy/tests/Service/ShellServiceTest.php
index 5fe54cff5..c33e38827 100644
--- a/legacy/tests/Service/ShellServiceTest.php
+++ b/legacy/tests/Service/ShellServiceTest.php
@@ -7,9 +7,13 @@
 use PHPUnit\Framework\TestCase;
 use Platformsh\Cli\Exception\ProcessFailedException;
 use Platformsh\Cli\Service\Shell;
+use Platformsh\Cli\Tests\HasTempDirTrait;
+use Symfony\Component\Process\Exception\ProcessStartFailedException;
 
 class ShellServiceTest extends TestCase
 {
+    use HasTempDirTrait;
+
     /**
      * Test Shell::execute().
      */
@@ -47,4 +51,27 @@ public function testMustExecute(): void
         $this->expectException(ProcessFailedException::class);
         $shell->mustExecute(['which', 'nonexistent']);
     }
+
+    /**
+     * Test Shell::execute() when the process cannot start, so has no exit code.
+     */
+    public function testExecuteStartFailure(): void
+    {
+        $this->tempDirSetUp();
+        assert($this->tempDir !== null);
+
+        // A phar:// directory passes is_dir() but cannot be used by proc_open().
+        $archive = new \PharData($this->tempDir . '/test.tar');
+        $archive->addFromString('dir/file.txt', 'test');
+        $dir = 'phar://' . $this->tempDir . '/test.tar/dir';
+
+        $shell = new Shell();
+        $this->assertFalse($shell->execute(['pwd'], $dir));
+        try {
+            $shell->mustExecute(['pwd'], $dir);
+            $this->fail('Expected a ProcessStartFailedException');
+        } catch (ProcessStartFailedException $e) {
+            $this->assertFalse($shell->exceptionMeansCommandDoesNotExist($e));
+        }
+    }
 }