๐Ÿ” CVE Alert

CVE-2026-33130

MEDIUM 6.5

Uptime Kuma: SSTI in Notification Templates Allows Arbitrary File Read (Incomplete Fix for GHSA-vffh-c9pq-4crh)

CVSS Score
6.5
EPSS Score
0.0%
EPSS Percentile
8th

Uptime Kuma is an open source, self-hosted monitoring tool. In versions 1.23.0 through 2.2.0, the fix from GHSA-vffh-c9pq-4crh doesn't fully work to preventServer-side Template Injection (SSTI). The three mitigations added to the Liquid engine (root, relativeReference, dynamicPartials) only block quoted paths. If a project uses an unquoted absolute path, attackers can still read any file on the server. The original fix in notification-provider.js only constrains the first two steps of LiquidJS's file resolution (via root, relativeReference, and dynamicPartials options), but the third step, the require.resolve() fallback in liquid.node.js has no containment check, allowing unquoted absolute paths like /etc/passwd to resolve successfully. Quoted paths happen to be blocked only because the literal quote characters cause require.resolve('"/etc/passwd"') to throw a MODULE_NOT_FOUND error, not because of any intentional security measure. This issue has been fixed in version 2.2.1.

CWE CWE-98 CWE-1336
Vendor louislam
Product uptime-kuma
Published Mar 20, 2026
Last Updated Mar 20, 2026
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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None

Affected Versions

louislam / uptime-kuma
>= 1.23.0, < 2.2.1

References

NVD โ†— CVE.org โ†— EPSS Data โ†—
github.com: https://github.com/louislam/uptime-kuma/security/advisories/GHSA-v832-4r73-wx5j github.com: https://github.com/advisories/GHSA-vffh-c9pq-4crh github.com: https://github.com/louislam/uptime-kuma/releases/tag/2.2.1