Medium severity · published Oct 26, 2026
CVE-2026-116516
Insufficient length validation when parsing Zoom chat transcriptions
New
6.5
CVSS
0.4%
EPSS
No
On KEV
Description
Mattermost versions <=11.9 11.1.9 11.5.8 11.10.7.0 fail to validate Zoom chat line length before slicing which allows an authenticated attacker to crash the Agents plugin via summarizing a Zoom chat transcription containing short continuation lines. Mattermost Advisory ID: MMSA-2026-00723
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 30% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MA
Mattermost · Mattermost
<=11.9 11.1.9 11.5.8 11.10.7.0 through <=11.9 11.1.9 11.5.8 11.10.7.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-116516
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-116516
mattermost.com
https://mattermost.com/security-updates
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