Vulnerability · Published Aug 13, 2026 · Assigned by VulnCheck
CVE-2026-73038NodeBB < 4.15.0 Stored XSS via ActivityPub emoji tag.icon.url and tag.name
Medium 6.1
In plain English
A medium-severity cross-site scripting in NodeBB from NodeBB. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 16% of all known vulnerabilities).
Severity (CVSS 3.1)6.1Medium
Exploit odds (30 days)0.2%top 84.0% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official description
NodeBB before 4.15.0 contains a stored cross-site scripting vulnerability in the renderEmoji function that fails to escape tag.icon.url and tag.name attributes. Attackers can deliver malicious ActivityPub Create/Note objects with crafted emoji tags to inject arbitrary HTML and JavaScript into stored post content, executing code in all viewers' browsers.
Affected products (as reported)
Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
References
- Researcher Disclosure technical-description, issue-tracking
- NodeBB 4.15.0 Release Notes release-notes
- Patch Commit patch
- https://www.vulncheck.com/advisories/nodebb-stored-xss-via-activitypub-emoji-tag-icon-url-and-tag-name third-party-advisory