Cross-site Scripting (XSS) Affecting metaflow-service package, versions <2.6.1-r3


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

EPSS
0.31% (23rd percentile)

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  • Snyk IDSNYK-CHAINGUARDLATEST-METAFLOWSERVICE-20341502
  • published1 Oct 2026
  • disclosed13 Oct 2026

Introduced: 1 Oct 2026

NewCVE-2026-49264  (opens in a new tab)
CWE-79  (opens in a new tab)

How to fix?

Upgrade Chainguard metaflow-service to version 2.6.1-r3 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream metaflow-service package and not the metaflow-service package as distributed by Chainguard. See How to fix? for Chainguard relevant fixed versions and status.

OAuthLib is an implementation of the OAuth request-signing logic for Python 3.6+. From 0.6.1 until 4.0.0, OAuthLib's RevocationEndpoint in oauthlib/oauth2/rfc6749/endpoints/revocation.py reflects an unvalidated callback request parameter into success and error response bodies when enable_jsonp=True. The callback can come from the query string or request body and is used without restricting it to a legal JavaScript function name. A browser application that loads the revocation response as trusted JSONP and permits attacker influence over callback can therefore execute attacker-controlled JavaScript in the including application's origin, with access to its DOM and script-accessible data. The feature is disabled by default, so only deployments that explicitly enable JSONP are affected. This issue is fixed in version 4.0.0.

CVSS Base Scores

version 3.1