CVE-2026-12882: falha de média gravidade em Mattermost
Mattermost Markdown autolink parsing denial of service
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Aviso por e-mail quando ela entrar no KEV, ganhar PoC pública ou subir de nota.
13Vexday Risk Score
Sem sinal de exploração. Nenhum artefato público de exploração conhecido até agora.
ssvc Trackcvss 4.3epss 0.4%
Mattermost versions 11.9.x <= 11.9.0, 11.8.x <= 11.8.4, 11.7.x <= 11.7.7, 10.11.x <= 10.11.22 fail to parse Markdown autolinks with unmatched trailing closing parentheses in linear time, which allows an authenticated user with permission to create posts to cause excessive server CPU consumption and degrade availability for other users via specially crafted post or message attachment content. Mattermost Advisory ID: MMSA-2026-00703
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
Produtos afetados
Mattermost · MattermostCVEs relacionadas — Mattermost
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Referências
https://mattermost.com/security-updates