CVE-2026-21726 (GCVE-0-2026-21726)

Vulnerability from cvelistv5 – Published: 2026-04-15 19:24 – Updated: 2026-04-15 20:01
VLAI?
Title
Loki Path Traversal - CVE-2021-36156 Bypass
Summary
The CVE-2021-36156 fix validates the namespace parameter for path traversal sequences after a single URL decode, by double encoding, an attacker can read files at the Ruler API endpoint /loki/api/v1/rules/{namespace} Thanks to Prasanth Sundararajan for reporting this vulnerability.
Severity ?
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Assigner
References
Impacted products
Vendor Product Version
Grafana Loki Affected: 2.3.0 , < 3.5.9 (semver)
Create a notification for this product.
Date Public ?
2026-04-15 19:20
Show details on NVD website
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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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