CVE-2026-86049 | BDVDB-2026-375797 Detail
jupyter-serverjupyter_server
Description#
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.
Impact#
Per CVSS v3.1: confidentiality impact high, integrity impact high, availability impact high. Attack vector: network.
Weaknesses#
- CWE-532 Insertion of Sensitive Information into Log File
References#
- https://github.com/jupyter-server/jupyter_server/security/advisories/GHSA-c3mw-737p-c7g2
- https://github.com/jupyter-server/jupyter_server/pull/1681
- https://github.com/jupyter-server/jupyter_server/commit/52513529af7096e622c00911b17627b266294717
- https://github.com/jupyter-server/jupyter_server/releases/tag/v2.21.0
Exploit#
No public exploit known
History#
- Version 1Record published in the CVE List.
- Version 2Most recent update recorded in the CVE List.