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PT-2026-41657

🗓️ 18 May 2026 00:00:00Reported by Positive TechnologiesType 
ptsecurity
 ptsecurity
🔗 dbugs.ptsecurity.com👁 28 Views

Mattermost fails to validate the requested header on burn-on-read reveal, enabling authenticated members to force reveal via a crafted image tag.

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30 Jul 2026 00:00Current
5.8Medium risk
Vulners AI Score5.8
CVSS 3.14.3
EPSS0.00157
SSVC
28