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HIGH · 7.3

CVE-2026-43939

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 ...

Vulnerability Description

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.

CVSS Score

7.3

HIGH

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE

Related Weaknesses (CWE)

CWE-116CWE-79CWE-80

References

FAQ

What is CVE-2026-43939?

CVE-2026-43939 is a vulnerability with a CVSS score of 7.3 (HIGH). 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 ...

How severe is CVE-2026-43939?

CVE-2026-43939 has been rated HIGH with a CVSS base score of 7.3/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-43939?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.