Critical severity · published Feb 4, 2026
CVE-2026-25519
OpenSlides has incorrect access control vulnerability in authentication service
9.8
CVSS
0.6%
EPSS
No
On KEV
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 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 46% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
OP
OpenSlides · OpenSlides
< 4.2.29 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-25519
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-25519
Product
https://github.com/OpenSlides/OpenSlides/releases/tag/4.2.29
Patch
https://github.com/OpenSlides/OpenSlides/security/advisories/GHSA-vv4h-8wfc-pf8c
Patch
https://github.com/OpenSlides/openslides-auth-service/commit/70c1aa9f5e1db59ec120ecce98d1c1169350a4ee
Issue Tracking
https://github.com/OpenSlides/openslides-auth-service/pull/889
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