← Vulnerability feed

Vulnerability record · CVE-2026-25519 · published 4 February 2026

CVE-2026-25519: Openslides improper access control vulnerability

Openslides · Openslides

OpenSlides is a free, web based presentation and assembly system for managing and projecting agenda, motions and elections of an assembly. Prior to version 4.2.29, OpenSlides supports local logins with username and password or an optionally configurable single sign on with SAML via an external IDP. For users synced to OpenSlides via an external IDP, there is an incorrect access control regarding the local login of these users. Users can successfully login using the local login form and the OpenSlides username of a SAML user and a trivial password. This password is valid for all SAML users. This issue has been patched in version 4.2.29.

9.8 CVSS 3.1 Critical EPSS 0.68% · top 49.6% CWE-284 · Improper access control
9.8CVSS 3.1 base score
0.68%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
4References
17 Jun 2026Last modified by NVD

Description

OpenSlides is a free, web based presentation and assembly system for managing and projecting agenda, motions and elections of an assembly. Prior to version 4.2.29, OpenSlides supports local logins with username and password or an optionally configurable single sign on with SAML via an external IDP. For users synced to OpenSlides via an external IDP, there is an incorrect access control regarding the local login of these users. Users can successfully login using the local login form and the OpenSlides username of a SAML user and a trivial password. This password is valid for all SAML users. This issue has been patched in version 4.2.29.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

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

References

LinkTags
https://github.com/OpenSlides/OpenSlides/releases/tag/4.2.29 ProductRelease Notes
https://github.com/OpenSlides/OpenSlides/security/advisories/GHSA-vv4h-8wfc-pf8c PatchVendor Advisory
https://github.com/OpenSlides/openslides-auth-service/commit/70c1aa9f5e1db59ec120ecce98d1c1169350a4ee Patch
https://github.com/OpenSlides/openslides-auth-service/pull/889 Issue Tracking

Track CVE-2026-25519 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.

8.9CVE-2020-26280Openslides cross-site scripting vulnerabilityOpenSlides is a free, Web-based presentation and assembly system for managing and projecting agenda, motions, and elections of assemblies. OpenSlides…EPSS 1.4%7.5CVE-2024-22892Openslides inadequate encryption strength vulnerabilityOpenSlides 4.0.15 was discovered to be using a weak hashing algorithm to store passwords.EPSS 0.25%7.5CVE-2024-22893Openslides improper privilege management vulnerabilityOpenSlides 4.0.15 verifies passwords by comparing password hashes using a function with content-dependent runtime. This can allow attackers to obtain…EPSS 0.36%6.5CVE-2025-30343Openslides path traversal vulnerabilityA directory traversal issue was discovered in OpenSlides before 4.2.5. Files can be uploaded to OpenSlides meetings and organized in folders. The int…EPSS 0.47%6.1CVE-2025-30342Openslides cross-site scripting vulnerabilityAn XSS issue was discovered in OpenSlides before 4.2.5. When submitting descriptions such as Moderator Notes or Agenda Topics, an editor is shown tha…EPSS 0.26%4.1CVE-2025-30345Openslides cross-site scripting vulnerabilityAn issue was discovered in OpenSlides before 4.2.5. When creating new chats via the chat_group.create action, the user is able to specify the name of…EPSS 0.28%3.7CVE-2025-30344Openslides observable discrepancy vulnerabilityAn issue was discovered in OpenSlides before 4.2.5. During login at the /system/auth/login/ endpoint, the system's response times differ depending on…EPSS 0.32%7.8CVE-2026-81963Windows Update Stack link-following privilege escalationWindows Update Stack resolves links improperly before accessing files, a link-following flaw (CWE-59) compounded by improper access control (CWE-284)…KEVEPSS 0.39%analysed

Source: NIST National Vulnerability Database (record CVE-2026-25519), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.