SB20261110267 - Path traversal in Mako

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Main Vulnerability Database SB20261110267

SB20261110267 - Path traversal in Mako

Published: November 10, 2026

Security Bulletin ID SB20261110267
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Remote access
Highest impact Data manipulation

Breakdown by Severity

Medium 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Path traversal (CVE-ID: CVE-2026-102991)

CWE-ID: CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

CVSSv4: 8.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to disclose files readable by the application on the template directory's volume and potentially execute code from files containing Mako/Python template syntax.

The vulnerability exists due to path traversal in Mako's TemplateLookup and Template.__init__ when resolving user-controlled paths with posixpath but validating confinement with ntpath on Windows. A remote attacker can supply drive-letter paths such as C:/../../secret.txt through template names or include paths to bypass directory confinement and load files outside the configured template directory.


Remediation

Install update from vendor's website.

References