cve.bz

CVE-2026-4635

5.3 mediumEPSS 0.2%

Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to archive the channel before removing persistent notifications which allows authenticated user to crash the server via timing the creation of persistent notification message between the server deleting existing persistent notifications and archiving the channel.. Mattermost Advisory ID: MMSA-2026-00637

Severity

CVSS 3.1

5.3 medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS
0.2% chance of exploitation in the next 30 days; higher than 6% of CVEs (scores of 2026-10-31)
CWE
CWE-362
Published
Modified
Record from
the NVD, synced

Affected

Packages (OSV)

AdvisoryEcosystemPackageAffectedFixed in
GHSA-pg7c-462j-grxvGogithub.com/mattermost/mattermost-server>=11.6.0 <11.6.111.6.1
GHSA-pg7c-462j-grxvGogithub.com/mattermost/mattermost-server>=11.5.0 <11.5.411.5.4
GHSA-pg7c-462j-grxvGogithub.com/mattermost/mattermost-server>=11.4.0 <11.4.511.4.5
GHSA-pg7c-462j-grxvGogithub.com/mattermost/mattermost-server>=10.11.0 <10.11.1510.11.15
GO-2026-5820Gogithub.com/mattermost/mattermost-server>=10.11.0+incompatible <10.11.15+incompatible
>=11.4.0+incompatible <11.4.5+incompatible
>=11.5.0+incompatible <11.5.4+incompatible
>=11.6.0+incompatible <11.6.1+incompatible		10.11.15+incompatible, 11.4.5+incompatible, 11.5.4+incompatible, 11.6.1+incompatible

References

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