Home/CVE/OpenProject is an open-source, web-based project management software. Users of OpenProject versions prior to 16.6.5 and
CVE

CVE-2026-23646

OpenProject is an open-source, web-based project management software. Users of OpenProject versions prior to 16.6.5 and

OpenProject is an open-source, web-based project management software. Users of OpenProject versions prior to 16.6.5 and 17.0.1 have the ability to view and end their active sessions via Account Settings - Sessions. When deleting a session, it was not properly checked if the session belongs to the user.

As the ID that is used to identify these session objects use incremental integers, users could iterate requests using DELETE /my/sessions/:id and thus unauthenticate other users. Users did not have access to any sensitive information (like browser identifier, IP addresses, etc) of other users that are stored in the session. The problem was patched in OpenProject versions 16.6.5 and 17.0.1.

No known workarounds are available as this does not require any permissions or other that can temporarily be disabled.

MEDIUM · CVSS 6.5 EPSS 0.00062
Monitor
  • No active-exploitation, high-EPSS, or public-exploit signals - routine patching cadence
Sigma rules0 YARA rules0
⬡

Weakness Classification

CWE-488Exposure of Data Element to Wrong Session
▤

Affected Products & Versions

2
openproject< 16.6.5
openprojectall versions
▣

Scoring & Timeline

6.5
MEDIUM · CVSS v3.1 · security-advisories@github.com
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD19 Jan 2026 · 06:16 PM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
SSVC triage · cisa-vulnrichment
Exploitation
none
Automatable
no
Technical impact
partial
SSVC asks the questions that actually drive patch urgency: is it being exploited, can attacks be automated, and how total is the impact.
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References & Sources

3
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://github.com/opf/openproject/releases/tag/v16.6.5Release Notes
https://github.com/opf/openproject/releases/tag/v17.0.1Release Notes
https://github.com/opf/openproject/security/advisories/GHSA-w422-xf8f-v4vpVendor Advisory
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