CVE-2026-25126: high-severity vulnerability in polarnl PolarLearn
PolarLearn's unvalidated vote direction allows vote count manipulation
Published · Updated
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.1epss 0.4%
PolarLearn is a free and open-source learning program. Prior to version 0-PRERELEASE-15, the vote API route (`POST /api/v1/forum/vote`) trusts the JSON body’s `direction` value without runtime validation. TypeScript types are not enforced at runtime, so an attacker can send arbitrary strings (e.g., `"x"`) as `direction`. Downstream (`VoteServer`) treats any non-`"up"` and non-`null` value as a downvote and persists the invalid value in `votes_data`. This can be exploited to bypass intended business logic. Version 0-PRERELEASE-15 fixes the vulnerability.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N
Affected products
polarnl · PolarLearnRelated CVEs — polarnl PolarLearn
In the same product, most dangerous first.
CVE-2026-25222MEDIUMPolarLearn Affected by User Enumeration via Argon2 Timing Attack on Sign-In EndpointEPSS 0.5%CVE-2026-25885CRITICALPolarLearn allows Unauthenticated WebSocket access allows subscribing to and posting in arbitrary group chatsEPSS 0.3%CVE-2026-35610HIGHPolarLearn has a Server Action Admin Bypass in Account Management ActionsEPSS 0.3%CVE-2026-39322CRITICALPolarLearn: Any password authenticates banned accounts and grants API accessEPSS 0.2%CVE-2026-25221LOWPolarLearn has Multiple Login CSRFs via Missing OAuth state Parameter (GitHub & Google)EPSS 0.2%