Description
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.
Scores
CVSS v3
5.3
EPSS
0.0001
EPSS Percentile
3.4%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
partial
Details
CWE
CWE-22
Status
published
Products (3)
grafana/loki
< 3.6.4
grafana/loki
0 - 3.6.4Go
Grafana/Loki
2.3.0 - 3.5.9
Published
Apr 15, 2026
Tracked Since
Apr 16, 2026