CVE-2025-54463: Mattermost Confluence Plugin · Unchecked Error Condition
Affects Mattermost Confluence PluginSource CVE Database V5
Not known to be exploited · CVSS 5.9 Medium.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 22% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 11 Aug 2025
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 |
|---|---|---|
| Mattermost Mattermost Confluence Plugin | Affected
| Fixed in– |
AI-suggested
To mitigate CVE-2025-54463, European organizations should: 1) Upgrade the Mattermost Confluence Plugin to version 1.5.0 or later once the patch is released by the vendor, as this will address the improper handling of exceptional conditions. 2) Implement network-level protections such as Web Application Firewalls (WAFs) or API gateways to validate and filter incoming webhook requests, blocking malformed or suspicious payloads before they reach the plugin. 3) Restrict access to the webhook endpoint by IP whitelisting or VPN requirements to limit exposure to trusted sources only. 4) Monitor webhook endpoint logs for unusual patterns of invalid requests that could indicate attempted exploitation or reconnaissance. 5) Employ rate limiting on the webhook endpoint to prevent repeated request flooding that could lead to denial of service. 6) Conduct regular security assessments and penetration testing focused on integration points like webhooks to identify and remediate similar issues proactively. These steps go beyond generic advice by focusing on both patch management and network-level controls tailored to the plugin's operational context.
Description
Mattermost Confluence Plugin version <1.5.0 fails to handle unexpected request body which allows attackers to crash the plugin via constant hit to server webhook endpoint with an invalid request body.