CVE-2026-25222 (GCVE-0-2026-25222)
Vulnerability from cvelistv5 – Published: 2026-02-02 23:01 – Updated: 2026-02-04 21:09
VLAI
EPSS
VEX
Title
PolarLearn Affected by User Enumeration via Argon2 Timing Attack on Sign-In Endpoint
Summary
PolarLearn is a free and open-source learning program. In 0-PRERELEASE-15 and earlier, a timing attack vulnerability in the sign-in process allows unauthenticated attackers to determine if a specific email address is registered on the platform. By measuring the response time of the login endpoint, an attacker can distinguish between valid and invalid email addresses. This occurs because the server only performs the computationally expensive Argon2 password hashing if the user exists in the database. Requests for existing users take significantly longer (~650ms) than requests for non-existent users (~160ms).
Severity
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-02-04 21:08 UTC
CWE
- CWE-200 - Exposure of Sensitive Information to an Unauthorized Actor
Assigner
GitHub_M
CNA
References
2 references
| URL | Tags |
|---|---|
| https://github.com/polarnl/PolarLearn/security/ad… | x_refsource_CONFIRM |
| https://github.com/polarnl/PolarLearn/commit/6c27… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| polarnl | PolarLearn |
Affected:
<= 0-PRERELEASE-15
|
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Nomenclature
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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