Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
PAC4J (pac4j-core) versions before 5.7.10, and versions from 6.0.0-RC1 before 6.4.1, are vulnerable to cross-site request forgery. An attacker can host a crafted website that, when a logged-in user visits it, submits a forged request with a token that collides with the victim's CSRF token, since the token's hash can be computed without knowing the victim's token. This allows state-changing actions such as profile updates, password changes, and account linking without the user's consent. Upgrade pac4j-core to 5.7.10 or 6.4.1.
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 |
|---|---|---|---|---|
| 7.0 | High | 4.0 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N | CNA (CERT-PL) |
- CISA KEV Not listed.
- EPSS 0.0016, the 5th percentile, on 10 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Oct 2026, 14:17 UTC First seen by agentprime
- 31 Oct 2026, 14:17 UTC Confirmed by OSV