CVE-2026-73038 (GCVE-0-2026-73038)

Vulnerability from cvelistv5 – Published: 2026-08-13 18:41 – Updated: 2026-08-14 16:52 X_Open Source
VLAI
Title
NodeBB < 4.15.0 Stored XSS via ActivityPub emoji tag.icon.url and tag.name
Summary
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.
Severity
5.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
6.1 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-14 16:40 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 6106 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
NodeBB NodeBB Affected: 0 , < 4.15.0 (semver)
    cpe:2.3:a:nodebb:nodebb:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-08-11 00:00
Credits
George Chen
Show details on NVD website
To clipboard 

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