cve.bz

CVE-2026-72721

5.3 mediumEPSS 0.6%

Medium (5.3). EPSS 0.6% chance of exploitation in the next 30 days.

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.

Severity

CVSS 3.1

5.3 medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
EPSS
0.6% chance of exploitation in the next 30 days; higher than 47% of CVEs (scores of 2026-10-31)
CWE
CWE-178
Published
Modified
Record from
the NVD, synced

References

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