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Fencer Intel
medium 6.5

CVE-2026-23646 json

OpenProject users can delete other user's session, causing them to be logged out

published 9mo ago modified 4mo ago also EUVD-2026-3308

cvss
6.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 31%
public exploits
0
none known

Summary

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.

Patch / fix

  • openproject openproject 16.6.5

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CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
9mo ago

Exploit prediction

0.37% chance of exploitation in the next 30 days, higher than 31% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected products

  • opf openproject

Classification

Weakness
  • CWE-488 Exposure of Data Element to Wrong Session

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.