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.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
None
No privileges needed
User Interaction
Passive
Minimal interaction
Impact Assessment
Confidentiality
None
No data leak
Integrity
None
No data modification
Availability
None
No disruption
CVSS Vector v4.0
Weakness Type (CWE)
References 4
https://github.com/NodeBB/NodeBB/commit/c0d94a217edcafcdb9b3920a6e80935194bcb19e
disclosure@vulncheck.com
https://github.com/NodeBB/NodeBB/issues/14601
disclosure@vulncheck.com
https://github.com/NodeBB/NodeBB/releases/tag/v4.15.0
disclosure@vulncheck.com
https://www.vulncheck.com/advisories/nodebb-stored-xss-via-activitypub-emoji-ta…
disclosure@vulncheck.com