CVE-2026-27934highCWE-201

CVE-2026-27934: high-severity vulnerability in discourse

Discourse leaks private topic title and post excerpt via user action API endpoint

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36Vexday Risk Score

Patch soon. It has a working public exploit.

ssvc Attendcvss 8.7epss 1.2%
Discourse is an open-source discussion platform. Versions prior to 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 have a lack of visibility checks with a user action API endpoint that results in disclosure of the title and post excerpt to unauthorized users, leading to information disclosure. Versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 contain a patch. No known workarounds are available.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
Affected products
discourse · discourse
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