Medium severity · published Oct 26, 2026
CVE-2026-93850
Unbounded memory consumption during PDF text extraction
New
6.5
CVSS
0.4%
EPSS
No
On KEV
Description
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
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 32% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MA
Mattermost · Mattermost
11.9.0 through 11.9.1; 11.8.0 through 11.8.5; 11.7.0 through 11.7.10; 11.10.0 through 11.10.1 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-93850
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-93850
mattermost.com
https://mattermost.com/security-updates
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