CVE-2026-13411: Mattermost · Unchecked Error Condition
Affects MattermostSource CVE Database V5
Not known to be exploited · CVSS 4.3 Medium.
Data as of 26 Oct 2026, 19:04 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 24% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Limited control over the software or limited information exposure
CISA SSVC assessment, 2026-10-22.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:LExploitation evidence
Disclosed: evidence found.
CVE published 22 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 applied, restrict access to the Playbooks import functionality to trusted users only to reduce risk.
Description
Mattermost versions 11.7.0 through 11.7.11 contain a vulnerability in the Playbooks plugin where null elements are not properly validated during the decoding of playbook import conditions. This flaw allows an authenticated attacker to crash the Playbooks plugin instance-wide by submitting a crafted import request with a null condition.