CVE-2026-25221 PolarLearn has Multiple Login CSRFs via Missing OAuth state Parameter (GitHub & Google)
Attackers can force victims to log into attacker-controlled accounts via missing OAuth state validation, causing data loss and information disclosure.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-25221?
CVE-2026-25221 is a low-severity vulnerability in polarnl PolarLearn, published on 2 Feb 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
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.
Weakness: CWE-352
Which versions are affected by CVE-2026-25221?
It affects 1 product.
Products include Polarlearn Polarlearn.
How do I fix CVE-2026-25221?
No fix has been published for CVE-2026-25221 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-25221 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-25221 exists.
Other vulnerabilities in polarnl PolarLearn
- CVE-2026-25885 PolarLearn allows Unauthenticated WebSocket access allows subscribing to and posting in arbitrary group chats
- CVE-2026-39322 PolarLearn: Any password authenticates banned accounts and grants API access
- CVE-2026-35610 PolarLearn has a Server Action Admin Bypass in Account Management Actions
- CVE-2026-25126 PolarLearn's unvalidated vote direction allows vote count manipulation
- CVE-2026-25222 PolarLearn Affected by User Enumeration via Argon2 Timing Attack on Sign-In Endpoint
Sources
Also known as GHSA-fhhm-574m-7rpw.