CVE-2026-25222

PolarLearn Affected by User Enumeration via Argon2 Timing Attack on Sign-In Endpoint

HIGH
7.5
CVSS Score
Published: February 2, 2026 at 11:01 PM UTC
Updated: June 17, 2026 at 10:24 AM UTC
2 products affected across 2 vendorsPolarlearnPolarLearn

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Severity
HIGH7.5
Exploit prediction
EPSS 0.5%
SSVC
PoC

Description

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).

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v ≤ 0-PRERELEASE-15

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (2)

SSVC — Action Prioritization

SSVCPoCNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-200

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