← Vulnerability feed

Vulnerability record · CVE-2026-25885 · published 9 February 2026

CVE-2026-25885: Polarlearn improper authorization vulnerability

Polarlearn · Polarlearn

PolarLearn is a free and open-source learning program. In 0-PRERELEASE-16 and earlier, the group chat WebSocket at wss://polarlearn.nl/api/v1/ws can be used without logging in. An unauthenticated client can subscribe to any group chat by providing a group UUID, and can also send messages to any group. The server accepts the message and stores it in the group’s chatContent, so this is not just a visual spam issue.

10.0 CVSS 4.0 Critical EPSS 0.42% · top 66.2% CWE-285 · Improper authorizationCWE-306 · Missing authentication for critical function
10.0CVSS 4.0 base score
0.42%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
2References, 1 tagged exploit
17 Jun 2026Last modified by NVD

Description

PolarLearn is a free and open-source learning program. In 0-PRERELEASE-16 and earlier, the group chat WebSocket at wss://polarlearn.nl/api/v1/ws can be used without logging in. An unauthenticated client can subscribe to any group chat by providing a group UUID, and can also send messages to any group. The server accepts the message and stores it in the group’s chatContent, so this is not just a visual spam issue.

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://github.com/polarnl/PolarLearn/commit/3ba588fda0d3f8e238483a20772719f27e52e79f Patch
https://github.com/polarnl/PolarLearn/security/advisories/GHSA-gvjm-5pw7-6c8c ExploitVendor Advisory

Track CVE-2026-25885 inside VULONE

Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.

Start free Open in platform

Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

9.2CVE-2026-39322Polarlearn improper authentication vulnerabilityPolarLearn is a free and open-source learning program. In 0-PRERELEASE-15 and earlier, POST /api/v1/auth/sign-in creates a valid session for banned a…EPSS 0.42%8.8CVE-2026-35610Polarlearn improper authorization vulnerabilityPolarLearn is a free and open-source learning program. In 0-PRERELEASE-14 and earlier, setCustomPassword(userId, password) and deleteUser(userId) in …EPSS 0.44%7.1CVE-2026-25126Polarlearn improper input validation vulnerabilityPolarLearn 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 JS…EPSS 0.38%6.3CVE-2026-25222Polarlearn information exposure vulnerabilityPolarLearn is a free and open-source learning program. In 0-PRERELEASE-15 and earlier, a timing attack vulnerability in the sign-in process allows un…EPSS 0.44%2.3CVE-2026-25221Polarlearn cross-site request forgery vulnerabilityPolarLearn is a free and open-source learning program. In 0-PRERELEASE-15 and earlier, the OAuth 2.0 implementation for GitHub and Google login provi…EPSS 0.22%8.8CVE-2026-58704Android Cellular Modem improper authorization allows adjacent privilege escalationAndroid's Cellular Modem component contains a logic error that bypasses permission checks, allowing an attacker within radio/adjacent range to escala…KEVEPSS 0.59%analysed9.8CVE-2021-28799QNAP HBS 3 improper authorization allows remote loginQNAP Hybrid Backup Sync 3 (HBS 3) contains an improper authorization flaw that lets remote attackers log in to the NAS device. The issue affects mult…KEVEPSS 78%analysed

Source: NIST National Vulnerability Database (record CVE-2026-25885), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.