CVE-2026-33393
- Source
- https://cve.org/CVERecord?id=CVE-2026-33393
- Import Source
- https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-33393.json
- JSON Data
- https://api.osv.dev/v1/vulns/CVE-2026-33393
- Aliases
-
- BIT-discourse-2026-33393
- GHSA-95r5-p6qr-hgw6
- Published
- 2026-03-19T22:04:26Z
- Modified
- 2026-09-30T03:47:23Z
- Severity
-
- 4.3 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N CVSS Calculator
- Summary
- Discourse fixes loose hostname matching in spam host allowlist
- Details
-
Discourse is an open-source discussion platform. Prior to versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2, the
allowed_spam_host_domainscheck usedString#end_with?without domain boundary validation, allowing domains likeattacker-example.comto bypass spam protection whenexample.comwas allowlisted. Versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 require exact match or proper subdomain match (preceded by.) to prevent suffix-based bypass ofnewuser_spam_host_threshold. No known workarounds are available. - Database specific
{ "cna_assigner": "GitHub_M", "cwe_ids": [ "CWE-284" ], "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33393.json", "unresolved_ranges": [ { "extracted_events": [ { "introduced": "2026.1.0-latest" }, { "fixed": "2026.1.2" }, { "introduced": "2026.2.0-latest" }, { "fixed": "2026.2.1" }, { "introduced": "= 2026.3.0-latest" }, { "last_affected": "= 2026.3.0-latest" } ], "source": "AFFECTED_FIELD" } ] }- References
-
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33393.json
- https://github.com/discourse/discourse/security/advisories/GHSA-95r5-p6qr-hgw6
- https://nvd.nist.gov/vuln/detail/CVE-2026-33393
- https://github.com/discourse/discourse/commit/80b19c15fe9c7bc890d1a54f454c8446312ac6d2
- https://github.com/discourse/discourse/commit/d8467b9fbb3d9ed6047b4e508d3fef88a37b8a02
- https://github.com/discourse/discourse/commit/f99099cfbc6b76fe39d6fa2daa48efd69497fb8e
Affected packages
Git / github.com/discourse/discourse
Affected versions
Other
esr
stable
v0.*
v0.8.0
v0.8.1
v0.8.2
v0.8.3
v0.8.4
v0.8.5
v0.8.6
v0.8.7
v0.8.8
v0.8.9
v0.9.0
v0.9.1
v0.9.2
v0.9.2.5
v0.9.2.6
v0.9.3
v0.9.4
v0.9.5
v0.9.5.1
v0.9.5.2
v0.9.6
v0.9.6.1
v0.9.6.3
v0.9.6.4
v0.9.7
v0.9.7.1
v0.9.7.2
v0.9.7.3
v0.9.7.4
v0.9.7.5
v0.9.7.6
v0.9.7.7
v0.9.7.8
v0.9.7.9
v0.9.8
v0.9.8.1
v0.9.8.10
v0.9.8.11
v0.9.8.2
v0.9.8.3
v0.9.8.4
v0.9.8.5
v0.9.8.6
v0.9.8.7
v0.9.8.8
v0.9.8.9
v0.9.9.1
v0.9.9.10
v0.9.9.11
v0.9.9.12
v0.9.9.13
v0.9.9.14
v0.9.9.15
v0.9.9.16
v0.9.9.17
v0.9.9.18
v0.9.9.2
v0.9.9.3
v0.9.9.4
v0.9.9.5
v0.9.9.6
v0.9.9.7
v0.9.9.8
v0.9.9.9
v1.*
v1.0.0
v1.1.0.beta2
v1.1.0.beta3
v1.1.0.beta4
v1.1.0.beta5
v1.1.0.beta6
v1.1.0.beta6b
v1.1.0.beta7
v1.1.0.beta8
v1.2.0.beta1
v1.2.0.beta2
v1.2.0.beta3
v1.2.0.beta4
v1.2.0.beta5
v1.2.0.beta6
v1.2.0.beta7
v1.2.0.beta8
v1.2.0.beta9
v1.3.0.beta1
v1.3.0.beta10
v1.3.0.beta11
v1.3.0.beta2
v1.3.0.beta3
v1.3.0.beta4
v1.3.0.beta5
v1.3.0.beta6
v1.3.0.beta9
v1.4.0.beta1
v1.4.0.beta10
v1.4.0.beta11
v1.4.0.beta12
v1.4.0.beta2
v1.4.0.beta3
v1.4.0.beta4
v1.4.0.beta5
v1.4.0.beta6
v1.4.0.beta7
v1.4.0.beta8
v1.4.0.beta9
v1.5.0.beta1
v1.5.0.beta10
v1.5.0.beta11
v1.5.0.beta12
v1.5.0.beta13
v1.5.0.beta13b
v1.5.0.beta14
v1.5.0.beta2
v1.5.0.beta4
v1.5.0.beta5
v1.5.0.beta6
v1.5.0.beta7
v1.5.0.beta8
v1.5.0.beta9
v1.6.0.beta1
v1.6.0.beta10
v1.6.0.beta11
v1.6.0.beta12
v1.6.0.beta2
v1.6.0.beta3
v1.6.0.beta4
v1.6.0.beta5
v1.6.0.beta6
v1.6.0.beta7
v1.6.0.beta8
v1.6.0.beta9
v1.7.0.beta1
v1.7.0.beta10
v1.7.0.beta11
v1.7.0.beta2
v1.7.0.beta3
v1.7.0.beta4
v1.7.0.beta5
v1.7.0.beta6
v1.7.0.beta7
v1.7.0.beta8
v1.7.0.beta9
v1.8.0.beta1
v1.8.0.beta10
v1.8.0.beta11
v1.8.0.beta12
v1.8.0.beta13
v1.8.0.beta2
v1.8.0.beta3
v1.8.0.beta4
v1.8.0.beta5
v1.8.0.beta6
v1.8.0.beta7
v1.8.0.beta8
v1.8.0.beta9
v1.9.0.beta1
v1.9.0.beta10
v1.9.0.beta11
v1.9.0.beta12
v1.9.0.beta13
v1.9.0.beta14
v1.9.0.beta15
v1.9.0.beta16
v1.9.0.beta17
v1.9.0.beta2
v1.9.0.beta3
v1.9.0.beta4
v1.9.0.beta5
v1.9.0.beta6
v1.9.0.beta7
v1.9.0.beta8
v1.9.0.beta9
v2.*
v2.0.0.beta1
v2.0.0.beta10
v2.0.0.beta2
v2.0.0.beta3
v2.0.0.beta4
v2.0.0.beta5
v2.0.0.beta6
v2.0.0.beta7
v2.0.0.beta8
v2.0.0.beta9
v2.1.0.beta1
v2.1.0.beta2
v2.1.0.beta3
v2.1.0.beta4
v2.1.0.beta5
v2.1.0.beta6
v2.2.0.beta1
v2.2.0.beta10
v2.2.0.beta2
v2.2.0.beta3
v2.2.0.beta4
v2.2.0.beta5
v2.2.0.beta6
v2.2.0.beta7
v2.2.0.beta8
v2.2.0.beta9
v2.3.0.beta1
v2.3.0.beta10
v2.3.0.beta11
v2.3.0.beta2
v2.3.0.beta3
v2.3.0.beta4
v2.3.0.beta5
v2.3.0.beta6
v2.3.0.beta7
v2.3.0.beta8
v2.3.0.beta9
v2.4.0.beta1
v2.4.0.beta10
v2.4.0.beta11
v2.4.0.beta2
v2.4.0.beta3
v2.4.0.beta4
v2.4.0.beta5
v2.4.0.beta6
v2.4.0.beta7
v2.4.0.beta8
v2.4.0.beta9
v2.5.0.beta1
v2.5.0.beta2
v2.5.0.beta3
v2.5.0.beta4
v2.5.0.beta5
v2.5.0.beta6
v2.5.0.beta7
v2.6.0.beta1
v2.6.0.beta2
v2.6.0.beta3
v2.6.0.beta4
v2.6.0.beta5
v2.6.0.beta6
v2.7.0.beta1
v2.7.0.beta2
v2.7.0.beta3
v2.7.0.beta4
v2.7.0.beta5
v2.7.0.beta6
v2.7.0.beta7
v2.7.0.beta8
v2.7.0.beta9
v2.8.0.beta1
v2.8.0.beta10
v2.8.0.beta11
v2.8.0.beta2
v2.8.0.beta3
v2.8.0.beta4
v2.8.0.beta5
v2.8.0.beta6
v2.8.0.beta7
v2.8.0.beta8
v2.8.0.beta9
v2.9.0.beta1
v2.9.0.beta10
v2.9.0.beta11
v2.9.0.beta12
v2.9.0.beta13
v2.9.0.beta14
v2.9.0.beta2
v2.9.0.beta3
v2.9.0.beta4
v2.9.0.beta5
v2.9.0.beta6
v2.9.0.beta7
v2.9.0.beta8
v2.9.0.beta9
v2025.*
v2025.12.0-latest
v2026.*
v2026.1.0
v2026.1.0-latest
v2026.1.1
v2026.2.0
v2026.2.0-latest
v2026.3.0-latest
v3.*
v3.0.0.beta15
v3.0.0.beta16
v3.1.0.beta1
v3.1.0.beta2
v3.1.0.beta3
v3.1.0.beta4
v3.1.0.beta5
v3.1.0.beta6
v3.1.0.beta7
v3.1.0.beta8
v3.2.0.beta1
v3.2.0.beta2
v3.2.0.beta3
v3.2.0.beta4
v3.2.0.beta5
v3.3.0.beta1
v3.3.0.beta2
v3.3.0.beta3
v3.3.0.beta4
v3.3.0.beta5
v3.3.0.beta6
v3.4.0.beta1
v3.4.0.beta2
v3.4.0.beta3
v3.4.0.beta4
v3.5.0.beta1
v3.5.0.beta2
v3.5.0.beta3
v3.5.0.beta4
v3.5.0.beta5
v3.5.0.beta6
v3.5.0.beta7
v3.5.0.beta8
v3.5.0.beta9
v3.6.0.beta1
v3.6.0.beta2