CVE-2026-3114 - Vulnerability Details - OpenCVE

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

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Exploitation none

Automatable no

Technical Impact partial

No data.

No data.

No data.

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References

Link	Providers
https://mattermost.com/security-updates

History

Thu, 26 Mar 2026 18:15:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Thu, 26 Mar 2026 16:45:00 +0000

Type	Values Removed	Values Added
Description		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
Title		Zip Bomb Denial of Service via Unrestricted Archive Decompression
Weaknesses		CWE-409
References		https://mattermost.com/security-updates
Metrics		cvssV3_1 `{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}`

MITRE

Status: PUBLISHED

Assigner: Mattermost

Published: 2026-03-26T16:21:19.421Z

Updated: 2026-03-26T17:51:14.833Z

Reserved: 2026-02-24T11:01:47.197Z

Link: CVE-2026-3114

Vulnrichment

Updated: 2026-03-26T17:47:26.384Z

NVD

Status : Received

Published: 2026-03-26T17:16:42.480

Modified: 2026-03-26T17:16:42.480

Link: CVE-2026-3114

Redhat

No data.

OpenCVE Enrichment

No data.

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