yanchenyu360

GitHub · Repository owner · Source ID 248167707
Source profile

Source-scoped identity with 1 associated PoC and 1 linked vulnerability.

Showing 1 PoC on this page

GitHub

yanchenyu360/CVE-2026-41940-Security-Patch

Repository PoC0Created 2026-08-13ScannerCVE-2026-419404 files

34.9 KiB

GitHubPoC details
Analysisdeepseek-v4-pro:cloud ·

Technical assessment

A C++ program that applies a temporary, unofficial patch to cPanel/WHM installations to mitigate CVE-2026-41940. It modifies Perl source files to add input sanitization, purges existing malicious session files, and restarts services. It does not exploit the vulnerability.

Backdoor review

No backdoor observed in reviewed code

The repository contains a C++ source file (payload withheld) and a payload withheld that implement a local privilege-escalation patch for CVE-2026-41940, an authentication bypass in cPanel/WHM. The code requires root/Administrator privileges, backs up target Perl files, inserts sanitization subroutines to filter control characters from session data, purges existing malicious session files, and restarts cPanel services. All behavior is consistent with the disclosed purpose of applying a temporary security patch. No concealed network calls, data exfiltration, unrelated payload execution, or deceptive behavior was observed.

ClassificationScanner
Model confidence95%
AuthenticationNot required
LanguagesC++
Target softwarecPanelWHM
Attack typesauthentication bypass
Evidence & reasoningClassification basis · observed behavior · safety review
Technical evidence

Classification basis and observed behavior

Classification basis

The artifact is a mitigation tool that modifies existing software to prevent exploitation of CVE-2026-41940. It does not contain any code to exercise or trigger the vulnerability; instead, it scans for and patches vulnerable files, and removes malicious session artifacts. This matches the definition of a scanner.

README.md:2-3cve_patch.cpp:706-758

Requirements

  • Must be executed with root/Administrator privileges on a system running cPanel/WHM.cve_patch.cpp:131-139
  • Requires OpenSSL development libraries for compilation.README.md:8

Observed behavior

  • Locates cPanel/WHM Perl source files (.pm, .pl) on the system.cve_patch.cpp:650-704
  • Backs up original files before modification.cve_patch.cpp:177-244
  • Injects Perl subroutines (_cve_2026_41940_sanitize, _cve_2026_41940_clean) and calls to them into session and authentication functions to strip control characters and newlines from session data, user, and password variables.cve_patch.cpp:246-383
  • Scans session directories and deletes files containing carriage returns, newlines, or control characters (0x00-0x1F, 0x7F).cve_patch.cpp:474-532
  • Restarts cPanel, cpsrvd, and whostmgrd services after patching.cve_patch.cpp:534-591
  • Verifies the patch by checking for the presence of injected sanitizer functions and a patch marker in the modified files.cve_patch.cpp:593-648
Safety-review evidence

Behaviors behind the backdoor verdict

Observables

File
Payload withheldMain patch implementation that modifies local cPanel Perl files and restarts services.cve_patch.cpp:1-758
File
Payload withheldDocumentation stating the patch is an unofficial temporary fix for CVE-2026-41940.README.md:1-8
Review boundaries

What the analysis did not establish

  • Evidence includes only two of four repository files; the other two files are omitted and their content is unknown.
  • The artifact is a temporary, unofficial patch and may not fully address all attack vectors.
  • Two files in the repository (unclassified, 14225 bytes total) were not provided as text and were not analyzed. Their content and potential behavior are unknown.
Model interpretation

This review is limited to the supplied PoC code and context. It does not assert that the code works or is safe to execute.