CVE-2026-43939

Summary

YetAnotherForum.NET (YAF.NET) is a C# ASP.NET forum. Prior to 4.0.5 and 3.2.12, the thread posting and reply feature accepts user-supplied content via a a post or reply that is stored server-side and later rendered back into the thread page without adequate HTML sanitization or contextual output encoding. This vulnerability is fixed in 4.0.5 and 3.2.12.

Affected Software

VendorProductVersion RangeStatus
YAFNETYAFNET>= 4.0.0-beta.1, < 4.0.5affected
YAFNETYAFNET< 3.2.12affected

Weaknesses

  • CWE-79: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
  • CWE-80: CWE-80: Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS)
  • CWE-116: CWE-116: Improper Encoding or Escaping of Output

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: poc
    • Automatable: no
    • Technical Impact: total

Additional References

References