Discourse: Onebox Domain Blocklist Bypass via Case-Sensitive Comparison
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
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| discourse | discourse | affected |
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No data.
No data.
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No CVSS v4.0
No CVSS v3.0
No CVSS v2
This CVE is not in the KEV list.
Exploit prediction score: < 1% (0.585% probability within 30 days)
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Discourse
Discourse discourse |
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| Vendors & Products |
Discourse
Discourse discourse |
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| Metrics |
ssvc
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| Description | 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. | |
| Title | Discourse: Onebox Domain Blocklist Bypass via Case-Sensitive Comparison | |
| Weaknesses | CWE-178 | |
| References |
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| Metrics |
cvssV3_1
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