CVE-2026-93850 PUBLISHED

Unbounded memory consumption during PDF text extraction

Assigner: Mattermost
Reserved: 18.09.2026 Published: 26.10.2026 Updated: 26.10.2026

Mattermost versions 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10, 11.10.x <= 11.10.1 fail to bind the volume of text extracted from an uploaded PDF which allows an authenticated user to exhaust server memory and cause a denial of service via a crafted PDF whose compressed content stream expands into a very large amount of text.. Mattermost Advisory ID: MMSA-2026-00769

Metrics

CVSS 3.1

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CVSS Score: 6.5

Attack Vector	Network	Scope	Unchanged
Attack Complexity	Low	Confidentiality Impact	None
Privileges Required	Low	Integrity Impact	None
User Interaction	None	Availability Impact	High

CVSS 3.1

Product Status

Vendor	Mattermost
Product	Mattermost
Versions	Default: unaffected affected from 11.9.0 to 11.9.1 (incl.) affected from 11.8.0 to 11.8.5 (incl.) affected from 11.7.0 to 11.7.10 (incl.) affected from 11.10.0 to 11.10.1 (incl.) Version 11.11.0 is unaffected Version 11.9.2 is unaffected Version 11.8.6 is unaffected Version 11.7.11 is unaffected Version 11.10.2 is unaffected

Solutions

Update Mattermost to versions 11.11.0, 11.9.2, 11.8.6, 11.7.11, 11.10.2 or higher.

Credits

alimursaliyev finder

References

MMSA-2026-00769

Problem Types

CWE-409: Improper Handling of Highly Compressed Data (Data Amplification) CWE