What’s Vulnerable › Vulnerabilities

CVE-2026-72730: Discourse: Stored XSS chat-transcript username unescaped in Rich Text Editor

• Severity: high (CVSS 8.7 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.4% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-08-10 · updated 2026-09-08
• Weakness: CWE-79

Description

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, the Rich Text Editor rendered a chat-transcript username as HTML, allowing stored cross-site scripting. This issue is fixed in versions 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0.

Affected products

• discourse: before 2026.1.6; from 2026.5.0-latest, < 2026.5.2; from 2026.6.0-latest, < 2026.6.1

References

• https://github.com/discourse/discourse/commit/32920affe4ad97b461ca2ae2f664c5fefc374baf
• https://github.com/discourse/discourse/commit/3fb1e8ead0d4f48d2cf55c8110825c7e8a6a45f5
• https://github.com/discourse/discourse/commit/7eb35d076ab9b6a612e86182336ce9787ce402ea
• https://github.com/discourse/discourse/commit/9633b8ecaf5a99f0407f5261b9bd1a05f7dac529
• https://github.com/discourse/discourse/security/advisories/GHSA-wg48-qxjc-f459

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