GHSA-q453-638c-h4mr

ghsaUSosv

Mattermost Fails to Validate Remote Cluster Upload Sessions

view advisory published 2025-08-21Licence: CC-BY-4.0

Mattermost versions 10.8.x <= 10.8.3, 10.5.x <= 10.5.8, 9.11.x <= 9.11.17, 10.9.x <= 10.9.2, 10.10.x <= 10.10.0 fail to validate upload types in remote cluster upload sessions which allows a system admin to upload non-attachment file types via shared channels that could potentially be placed in arbitrary filesystem directories.

describes (1)

Related CVEs.

ID	severity	EPSS	exploitable	published
CVE-2025-49222US	medium6.8	0.30% (23rd)	—	2025-08-21
Mattermost versions 10.8.x <= 10.8.3, 10.5.x <= 10.5.8, 9.11.x <= 9.11.17, 10.9.x <= 10.9.2, 10.10.x <= 10.10.0 fail to validate upload types in remote cluster upload sessions whic…

references

External citations — patches, advisories, analysis.

https://github.com/mattermost/mattermostPACKAGE
https://mattermost.com/security-updatesWEB
https://nvd.nist.gov/vuln/detail/CVE-2025-49222ADVISORY
https://pkg.go.dev/vuln/GO-2025-3904WEB

scry

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