5.3

CVE-2026-72721

Discourse: Onebox Domain Blocklist Bypass via Case-Sensitive Comparison

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, Onebox::DomainChecker.is_blocked? compares hostnames and SiteSetting.blocked_onebox_domains entries case-sensitively, allowing an attacker to bypass configured Onebox domain restrictions by changing character casing in a redirect target hostname. This issue is fixed in versions 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0.
Daten sind bereitgestellt durch das CVE Programm von einer CVE Numbering Authority (CNA) (Unstrukturiert).
Herstellerdiscourse
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Produkt discourse
Version < 2026.1.6
Status affected
Version >= 2026.5.0-latest, < 2026.5.2
Status affected
Version >= 2026.6.0-latest, < 2026.6.1
Status affected
Version >= 2026.7.0-latest, < 2026.7.0
Status affected
VulnDex Vulnerability Enrichment
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Zu dieser CVE wurde keine Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.43% 0.354
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
security-advisories@github.com 5.3 3.9 1.4
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
CWE-178 Improper Handling of Case Sensitivity

The product does not properly account for differences in case sensitivity when accessing or determining the properties of a resource, leading to inconsistent results.

https://github.com/discourse/discourse/security/advisories/GHSA-3x7x-24rq-h5j6
https://github.com/discourse/discourse/pull/42091
https://github.com/discourse/discourse/pull/42092
https://github.com/discourse/discourse/pull/42093
https://github.com/discourse/discourse/pull/42094
https://github.com/discourse/discourse/commit/a3e10759fef47f03d450649bb51d9e84f4c68b8f
https://github.com/discourse/discourse/commit/c2eb6b0e5597d6f28f4be739b83300bc9c69e3cd
https://github.com/discourse/discourse/commit/caa615c371b1696982ee11ac8f3558f0f8ced584
https://github.com/discourse/discourse/commit/f503971d311b7b0dfdb751ee8cfd67e8cb99f5c5