Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
Listmonk versions up to and including 1.1.0 are affected. The backend does not validate the nonce value on requests, and the session cookie lacks a SameSite flag, so an attacker can lure a logged-in admin to a malicious page that makes cross-site requests and triggers script execution in the admin's browser, which can create a new admin account. The source gives few details on which browsers are affected. No fixed version is listed.
Not analysed yet
We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.
Severity and exploitation
| Score | Rating | CVSS | Vector | Source |
|---|---|---|---|---|
| 8.6 | High | 4.0 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N | CNA (GitHub_M) |
- CISA KEV Not listed.
- EPSS 0.0014, the 3rd percentile, on 13 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Oct 2026, 14:14 UTC First seen by agentprime
- 31 Oct 2026, 14:14 UTC Confirmed by OSV