CSRF in Polarlearn

CVE-2026-25221

PolarLearn is a free and open-source learning program. In 0-PRERELEASE-15 and earlier, the OAuth 2.0 implementation for GitHub and Google login providers is vulnerable to Login Cross-Site Request Forgery (CSRF). The application fails to implement and verify the state parameter during the authentication flow. This allows an attacker to pre-authenticate a session and trick a victim into logging into the attacker's account. Any data the victim then enters or academic progress they make is stored on the attacker's account, leading to data loss for the victim and information disclosure to the attacker.

Vulnerability class: CSRF (Cross-Site Request Forgery)

EPSS: 0.002 (10.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-25221?
CVE-2026-25221 is a high-severity vulnerability in Polarlearn, classified under Cross-Site Request Forgery (CSRF). CVSS score: 8.1/10. Published 2026-02-02.
How severe is CVE-2026-25221?
High severity. CVSS v3 base score is 8.1 out of 10.