CVE-2026-43937

YAF.NET: Pre-Handler Authorization Bypass on Admin Pages Enabling Blind SQL Execution via `/Admin/RunSql`

HIGH
8.8
CVSS Score
Published: May 12, 2026 at 02:00 PM UTC
Updated: June 17, 2026 at 10:50 AM UTC
1 product affected across 1 vendorYAFNET

Using YAFNET by YAFNET?

Get instant alerts when new vulnerabilities affect YAFNET - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
HIGH8.8
Exploit prediction
EPSS 0.5%
SSVC
PoC

Description

YetAnotherForum.NET (YAF.NET) is a C# ASP.NET forum. Prior to 4.0.5, Any admin OnPost… handler executes its side effects before the ResultFilterAttribute rewrites the response to a 302 to /Info/4. The most impactful abuse is /Admin/RunSql, whose OnPostRunQuery binds Editor from the POST body and passes it straight to IDbAccess.RunSql with no caller check, yielding arbitrary SQL execution for any low-privileged user. This vulnerability is fixed in 4.0.5.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 4.0.5
Affected range stops below 4.0.5, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

References (1)

SSVC — Action Prioritization

SSVCPoCNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

8.8HIGHGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-89CWE-841

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card