CVE-2026-73038

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.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/NodeBB/NodeBB/commit/c0d94a217edcafcdb9b3920a6e80935194bcb19e
https://github.com/NodeBB/NodeBB/issues/14601
https://github.com/NodeBB/NodeBB/releases/tag/v4.15.0
https://www.vulncheck.com/advisories/nodebb-stored-xss-via-activitypub-emoji-tag-icon-url-and-tag-name
https://github.com/NodeBB/NodeBB/issues/14601

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-13 19:17

Updated : 2026-08-14 17:20

NVD link : CVE-2026-73038

Mitre link : CVE-2026-73038

CVE.ORG link : CVE-2026-73038

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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