N8n vulnerabilities

n8n is an open source workflow automation platform. Prior to 1.123.76, 2.37.7, and 2.38.2, the legacy expression engine generated source text by calling the mutable global JSON.stringify while printing synthetic string literals and interpolating timezone data. An expression could replace JSON.stringify and cause later generated source to contain executable attacker-controlled code. The affected code-generation paths include packages/@n8n/expression-runtime/src/bridge/isolated-vm-bridge.ts and packages/@n8n/tournament/src/ExpressionBuilder.ts, and the issue does not affect the vm expression engine. This issue is fixed in versions 1.123.76, 2.37.7 and 2.38.2.

n8n is an open source workflow automation platform. Prior to 1.123.76, 2.37.7, and 2.38.2, the expression compiler sanitizer resolved through dynamically scoped this and did not reject reserved class member names. A class field named __sanitize could rebind the sanitizer and reach the Function constructor, enabling backend code execution and editor-preview JavaScript execution. The affected AST hook is PrototypeSanitizer in packages/workflow/src/expression-sandboxing.ts. This issue is fixed in versions 1.123.76, 2.37.7 and 2.38.2.

n8n is an open source workflow automation platform. Prior to 2.37.7 and 2.38.2, the OAuth Dynamic Client Registration endpoint bounded redirect_uris but accepted arbitrarily large client_name and grant_types values. An unauthenticated remote caller could repeatedly persist oversized values in oauth_clients and exhaust database storage. The affected validation is in packages/cli/src/modules/oauth-server/oauth-server.service.ts, including MAX_CLIENT_NAME_LENGTH and MAX_GRANT_TYPES. This issue is fixed in versions 2.37.7 and 2.38.2.

n8n is an open source workflow automation platform. Prior to 2.37.7 and 2.38.2, the Instance AI credential setup flow accepted a credential test or verification URL without checking that it matched the workflow node's origin. Attacker-controlled fetched content could influence that URL after a user injected it into the setup flow, causing authenticated requests, redirects, or probes to reach another origin. The affected logic includes packages/@n8n/instance-ai/src/tools/workflows/credential-utils.ts and the extractServiceOrigin origin derivation. This issue is fixed in versions 2.37.7 and 2.38.2.

n8n is an open source workflow automation platform. Prior to 2.37.7 and 2.38.1, the OAuth token endpoint bound an authorization code's first access token to the consented resource but did not bind its refresh token. Refreshing checked only that the requested resource was registered, not that it matched the original grant. An OAuth client approved for one workflow could substitute a different workflow URL in the resource parameter and obtain a valid token for an unapproved workflow accessible to the consenting user. This issue is fixed in versions 2.37.7 and 2.38.1.

n8n versions before 1.123.73, 2.35.4, and 2.36.2 contain an expression sandbox escape in the $fromAI handler. $fromAI resolved a caller-supplied placeholder name without requiring it to be an own property and admitted reserved keys; against a primitive input value it returned a live host-prototype reference. An attacker with workflow-build privilege can walk the prototype chain to the Function constructor and compile/execute arbitrary code in the main n8n process, leading to remote code execution.

n8n versions before 1.123.73, 2.35.4, and 2.36.2 contain a remote code execution vulnerability in the Git node. The node reset a fixed list of command-bearing configuration keys before each operation, but that list did not cover the content-filter and merge-driver key families. A repository with local configuration setting one of those keys together with a matching attribute pattern causes git to execute the configured command during an ordinary Add, Commit, Checkout, or Pull operation. The command runs as the n8n process user.