Leantime vulnerability

Leantime contains an OIDC login CSRF vulnerability in the verifyState() method that unconditionally returns true without validating state parameters. Attackers can craft malicious callback URLs with attacker-controlled authorization codes to perform session fixation, logging victims in as the attacker.

Published 6 Jul 2026Updated 17 Sep 20264 sources
CVSS 8.6

What happened

Leantime contains an OIDC login CSRF vulnerability in the verifyState() method that unconditionally returns true without validating state parameters. Attackers can craft malicious callback URLs with attacker-controlled authorization codes to perform session fixation, logging victims in as the attacker.

Affected versions

Leantime: 0 through 3.4.4 (semver) Fixed: See vendor advisory.

Why it matters

Review the vendor advisory and exposure of the affected product to determine operational impact.

Detection & mitigation

  • Apply vendor-provided updates or mitigations.
  • Review affected product exposure and access logs.

Public PoC references

No public PoC reference has passed the current publication threshold.