Source: jupyter-server Version: 2.20.0-3 X-Debbugs-CC: [email protected] Severity: important Tags: security upstream
Hi, The following vulnerability was published for jupyter-server. CVE-2026-86049[0]: | Jupyter Server is the backend for Jupyter web applications. Prior to | version 2.21.0, the 5xx request logging path in | jupyter_server/log.py copies the Referer header into a JSON header | block without applying the token scrubbing used for the request URI. | A request that returns HTTP 500 while the Referer contains a token- | bearing URL can therefore write that token to server logs in | plaintext. An attacker who can read those logs can recover the token | and use the affected user's Jupyter Server permissions. This issue | is fixed in version 2.21.0. If you fix the vulnerability please also make sure to include the CVE (Common Vulnerabilities & Exposures) id in your changelog entry. For further information see: [0] https://security-tracker.debian.org/tracker/CVE-2026-86049 https://www.cve.org/CVERecord?id=CVE-2026-86049 [1] https://github.com/jupyter-server/jupyter_server/security/advisories/GHSA-c3mw-737p-c7g2 [2] https://github.com/jupyter-server/jupyter_server/pull/1681 Please adjust the affected versions in the BTS as needed. Regards, Salvatore
