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

Description

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.

Scores

EPSS (exploitation in 30 days)

0.35% · top 71% of all CVEs (6 Nov 2026)

CISA SSVC

Exploitation: poc · Automatable: no · Technical impact: partial

The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.5.

Weakness

• CWE-98: Improper Control of Filename for Include/Require Statement in PHP Program ('PHP Remote File Inclusion') (opens in a new tab)All about CWE-98 and its CVEs
• CWE-1336: Improper Neutralization of Special Elements Used in a Template Engine (opens in a new tab)All about CWE-1336 and its CVEs

Affected products

• louislam · uptime-kuma

  • affected >= 1.23.0, < 2.2.1

References (3)

• https://github.com/louislam/uptime-kuma/security/advisories/GHSA-v832-4r73-wx5j (opens in a new tab)x_refsource_CONFIRM
• https://github.com/advisories/GHSA-vffh-c9pq-4crh (opens in a new tab)x_refsource_MISC
• https://github.com/louislam/uptime-kuma/releases/tag/2.2.1 (opens in a new tab)x_refsource_MISC

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2026-33130](https://trackcve.app/badge/CVE-2026-33130.svg)](https://trackcve.app/cve/CVE-2026-33130)

Record last updated 20 Mar 2026, 21:18 UTC.