CVE Vulnerabilities

CVE-2026-86049

Insertion of Sensitive Information into Log File

Published: Sep 17, 2026 | Modified: Sep 18, 2026
CVSS 3.x
N/A
Source:
NVD
CVSS 2.x
RedHat/V2
RedHat/V3
4.8 MODERATE
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:N/A:N
Ubuntu
MEDIUM
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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 users Jupyter Server permissions. This issue is fixed in version 2.21.0.

Weakness

The product writes sensitive information to a log file.

Potential Mitigations

References