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TI-2023-14373 Aliases CVE-2023-30538

Stored Cross-site Scripting via improper sanitization of svg files in Discourse

Priority LOW 26CWE-79Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Cross-site scripting
Confidentiality · integrity · availability
Low · Low · None
Fix status
No fix listed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-79.

Summary

Discourse is an open source platform for community discussion. Due to the improper sanitization of SVG files, an attacker can execute arbitrary JavaScript on the users’ browsers by uploading a crafted SVG file. This issue is patched in the latest stable and tests-passed versions of Discourse. Users are advised to upgrade. For users unable to upgrade there are two possible workarounds: enable CDN handing of uploads (and ensure the CDN sanitizes SVG files) or disable SVG file uploads by ensuring that the `authorized extensions` site setting does not include `svg` (or reset that setting to the default, by default Discourse doesn't enable SVG uploads by users).

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00364 30th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
discoursediscoursestable: < 3.0.3; beta: < 3.1.0.beta4—No fix listedCNA
  • discourse Vendordiscourse Affected stable: < 3.0.3; beta: < 3.1.0.beta4 Fixed in — No fix listed CNA

CPE configurations NVD · 5

CPEVersionsRoleVendor
cpe:2.3:a:discourse:discourse:*:*:*:*:stable:*:*:*up to 3.0.2Vulnerablediscourse
cpe:2.3:a:discourse:discourse:*:*:*:*:beta:*:*:*before 3.1.0Vulnerablediscourse
cpe:2.3:a:discourse:discourse:3.1.0:beta1:*:*:beta:*:*:*3.1.0 beta1Vulnerablediscourse
cpe:2.3:a:discourse:discourse:3.1.0:beta2:*:*:beta:*:*:*3.1.0 beta2Vulnerablediscourse
cpe:2.3:a:discourse:discourse:3.1.0:beta3:*:*:beta:*:*:*3.1.0 beta3Vulnerablediscourse
  • cpe:2.3:a:discourse:discourse:*:*:*:*:stable:*:*:* Versions up to 3.0.2 Vulnerable ·discourse
  • cpe:2.3:a:discourse:discourse:*:*:*:*:beta:*:*:* Versions before 3.1.0 Vulnerable ·discourse
  • cpe:2.3:a:discourse:discourse:3.1.0:beta1:*:*:beta:*:*:* Versions 3.1.0 beta1 Vulnerable ·discourse
  • cpe:2.3:a:discourse:discourse:3.1.0:beta2:*:*:beta:*:*:* Versions 3.1.0 beta2 Vulnerable ·discourse
  • cpe:2.3:a:discourse:discourse:3.1.0:beta3:*:*:beta:*:*:* Versions 3.1.0 beta3 Vulnerable ·discourse

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2023-30538

References

Advisory 1

  • TI-2021-19656 Denial of Service in discourse CVSS 3.1MEDIUM 6.8
  • TI-2024-36150 Potential Backup file leaked via Nginx in Discourse CVSS 3.1HIGH 7.5
  • TI-2021-18002 RCE via malicious SNS subscription payload CVSS 3.1CRITICAL 10.0
  • TI-2026-24651 Discourse: Open redirect via `sso_destination_url` cookie in `enter` CVSS 4.0MEDIUM 5.1
  • TI-2026-22278 Discourse leaks private topic title and post excerpt via user action API endpoint CVSS 4.0HIGH 8.7
  • TI-2023-24152 Unauthenticated access to new private chat messages in Discourse CVSS 3.1HIGH 7.5
See all 262 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences