CVE-2026-53962
Prior to 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, insufficient SVG sanitization in upload and user avatar handling could lead to cross-site scripting when a user visited specific URLs that are not normally part of community browsing.
Does this matter?
Lower severity and a low EPSS score (0.41%). Track it; it rarely justifies an emergency change on its own.
Description
Discourse is an open-source discussion platform. Prior to 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, insufficient SVG sanitization in upload and user avatar handling could lead to cross-site scripting when a user visited specific URLs that are not normally part of community browsing. This issue is fixed in versions 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5.
- CVSS 3.1
- 5.4 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
- EPSS
- 0.41% probability · 35th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-79
- Affected
- discourse/discourse
- Source
- security-advisories@github.com
References
- https://github.com/discourse/discourse/commit/3ee8343cd7f00d59d8513bee0a12e02d50bfc358Patch
- https://github.com/discourse/discourse/commit/810c2715799fd08b06fd6ffc664d9562fe9ea6ffPatch
- https://github.com/discourse/discourse/commit/92a699d89b84685b6fdd63cd0d0e371793c69dadPatch
- https://github.com/discourse/discourse/commit/b8ceb49f4ba52257be30eb3c2ce51a5bf03be5fePatch
- https://github.com/discourse/discourse/releases/tag/v2026.1.5Release Notes
- https://github.com/discourse/discourse/releases/tag/v2026.4.2Release Notes
- https://github.com/discourse/discourse/releases/tag/v2026.5.1Release Notes
- https://github.com/discourse/discourse/releases/tag/v2026.6.0Release Notes
- https://github.com/discourse/discourse/security/advisories/GHSA-jmcf-3367-78vvVendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.