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
Source GCVE Database
Not known to be exploited · CVSS 6.5 Medium.
Data as of 26 Oct 2026, 16:35 UTC
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 26 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| MattermostMattermost | Affected
| Fixed in– |
AI-suggested
Until a fix is available, restrict PDF uploads to trusted users or implement resource usage limits on PDF processing if possible.
Description
Mattermost versions 11.9.x up to 11.9.1, 11.8.x up to 11.8.5, 11.7.x up to 11.7.10, and 11.10.x up to 11.10.1 contain a vulnerability where the application fails to properly bind the volume of text extracted from an uploaded PDF. This flaw allows an authenticated user to cause a denial of service by uploading a crafted PDF whose compressed content stream expands into a very large amount of text, exhausting server memory.