cve.bz

CVE-2026-3114

6.5 mediumEPSS 0.4%

Medium (6.5) in mattermost mattermost server. EPSS 0.4% chance of exploitation in the next 30 days. Fixed in github.com/mattermost/mattermost/server/v8 10.11.12, 11.2.4, 11.3.2.

Mattermost versions 11.4.x <= 11.4.0, 11.3.x <= 11.3.1, 11.2.x <= 11.2.3, 10.11.x <= 10.11.11 fail to validate decompressed archive entry sizes during file extraction which allows authenticated users with file upload permissions to cause a denial of service via crafted zip archives containing highly compressed entries (zip bombs) that exhaust server memory.. Mattermost Advisory ID: MMSA-2026-00598

Severity

CVSS 3.1

6.5 medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS
0.4% chance of exploitation in the next 30 days; higher than 29% of CVEs (scores of 2026-10-31)
CWE
CWE-409
Published
Modified
Record from
the NVD, synced

Affected

Packages (OSV)

AdvisoryEcosystemPackageAffectedFixed in
GHSA-vhgh-g7x8-4rx8Gogithub.com/mattermost/mattermost/server/v8>=11.4.0 <11.4.111.4.1
GHSA-vhgh-g7x8-4rx8Gogithub.com/mattermost/mattermost/server/v8>=11.3.0 <11.3.211.3.2
GHSA-vhgh-g7x8-4rx8Gogithub.com/mattermost/mattermost/server/v8>=11.2.0 <11.2.411.2.4
GHSA-vhgh-g7x8-4rx8Gogithub.com/mattermost/mattermost/server/v8>=10.11.0 <10.11.1210.11.12
GHSA-vhgh-g7x8-4rx8Gogithub.com/mattermost/mattermost/server/v8>=8.0.0-20260105080200-d27a2195068d <8.0.0-20260217110922-b7d4a1f1f59b8.0.0-20260217110922-b7d4a1f1f59b
GO-2026-5663Gogithub.com/mattermost/mattermost-server>=10.11.0+incompatible <10.11.12+incompatible
>=11.2.0+incompatible <11.2.4+incompatible
>=11.3.0+incompatible <11.3.2+incompatible
>=11.4.0+incompatible <11.4.1+incompatible
10.11.12+incompatible, 11.2.4+incompatible, 11.3.2+incompatible, 11.4.1+incompatible
GO-2026-5663Gogithub.com/mattermost/mattermost-server/v5all versionsno fix published
GO-2026-5663Gogithub.com/mattermost/mattermost-server/v6all versionsno fix published
GO-2026-5663Gogithub.com/mattermost/mattermost/server/v8>=8.0.0-20260105080200-d27a2195068d <8.0.0-20260217110922-b7d4a1f1f59b8.0.0-20260217110922-b7d4a1f1f59b

References

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