CVE-2026-34828: listmonk: Active sessions remain valid after password reset and password change

Severity: high (CVSS 7.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-04-02 · updated 2026-07-24
Weakness: CWE-613

Description

listmonk is a standalone, self-hosted, newsletter and mailing list manager. From version 4.1.0 to before version 6.1.0, a session management vulnerability allows previously issued authenticated sessions to remain valid after sensitive account security changes, specifically password reset and password change. As a result, an attacker who has already obtained a valid session cookie can retain access to the account even after the victim changes or resets their password. This weakens account recovery and session security guarantees. This issue has been patched in version 6.1.0.

Affected products

knadh listmonk: from 4.1.0 before 6.1.0 — fixed in 6.1.0

How to fix

Upgrade to a fixed version: knadh listmonk 6.1.0. Check the vendor advisory for mitigations.

References

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