Vulnerability · Published Jun 9, 2025 · Assigned by GitHub_M
CVE-2025-49136listmonk's Sprig template Injection vulnerability leads to reading of Environment Variable for low privilege user
Critical 9.1
In plain English
A critical-severity security flaw in listmonk from knadh. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 1.6% (higher than 77% of all known vulnerabilities). Ready-made attack tooling exists: Metasploit. Fixed versions are available - upgrade the affected package.
Official description
listmonk is a standalone, self-hosted, newsletter and mailing list manager. Starting in version 4.0.0 and prior to version 5.0.2, the `env` and `expandenv` template functions which is enabled by default in Sprig enables capturing of env variables on host. While this may not be a problem on single-user (super admin) installations, on multi-user installations, this allows non-super-admin users with campaign or template permissions to use the `{{ env }}` template expression to capture sensitive environment variables. Users should upgrade to v5.0.2 to mitigate the issue.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/knadh/listmonk | 5.0.2 | GHSA-jc7g-x28f-3v3h |
| Go | github.com/knadh/listmonk | no fix listed | GO-2025-3745 |
Affected products (as reported)
Weakness: CWE-1336 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H
References
- https://github.com/knadh/listmonk/security/advisories/GHSA-jc7g-x28f-3v3h x_refsource_CONFIRM
- https://github.com/knadh/listmonk/commit/d27d2c32cf3af2d0b24e29ea5a686ba149b49b3e x_refsource_MISC
- https://github.com/knadh/listmonk/releases/tag/v5.0.2 x_refsource_MISC