SB2026013060 - Path traversal in Grafana Loki
Published: January 30, 2026
Security Bulletin ID
SB2026013060
Severity
Medium
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Information disclosure
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 security vulnerability.
1) Path traversal (CVE-ID: CVE-2026-21726)
The vulnerability allows a remote attacker to perform directory traversal attacks.
The vulnerability exists due to input validation error when processing directory traversal sequences within the "/loki/api/v1/rules/{namespace}" API endpoint. A remote attacker can send a specially crafted HTTP request and read arbitrary files on the system.
Note, the vulnerability exists due to incomplete fix for #VU64412 (CVE-2021-36156).
Remediation
Install update from vendor's website.