CVE-2026-104721

Path-traversal vulnerability in QOS.CH Sarl Logback-classic on Java (logback-classic module) allows path-traversal vulnerability. More specifically, an MDC-based discriminator value flows unsanitized into a nested FileAppender path, letting an attacker who influences that MDC value (e.g. via an HTTP header) create and append log files outside the intended directory. This issue affects Logback-classic: from 0.9.14 through 1.6.4. This vulnerability is similar to CVE-2026-19880 but involves other attack techniques.

CVSS

No CVSS.

References

Link	Resource
https://logback.qos.ch/news.html#1.6.5

Configurations

No configuration.

History

02 Oct 2026, 14:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-02 14:17

Updated : 2026-10-02 17:59

NVD link : CVE-2026-104721

Mitre link : CVE-2026-104721

CVE.ORG link : CVE-2026-104721

JSON object : View

Products Affected

No product.

CWE

CWE-22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

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