FrontAccounting up to 2.4.19 PHP File unique_name path traversal

Summaryinfo

A vulnerability, which was classified as critical, was found in FrontAccounting up to 2.4.19. This impacts an unknown function of the component PHP File Handler. Executing a manipulation of the argument unique_name can lead to path traversal. The identification of this vulnerability is CVE-2026-40521. The attack may be launched remotely. There is no exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in FrontAccounting up to 2.4.19. It has been declared as critical. This vulnerability affects some unknown functionality of the component PHP File Handler. The manipulation of the argument unique_name with an unknown input leads to a path traversal vulnerability. The CWE definition for the vulnerability is CWE-22. The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

FrontAccounting before 2.4.20 contains a path traversal vulnerability in the attachment upload handler that allows authenticated attackers to execute arbitrary code by uploading files with traversal sequences in the unique_name parameter. Attackers can supply path traversal sequences ../../../shell.php to write files outside the intended attachments directory into the web root, and by uploading PHP files without extension validation, achieve remote code execution as the web server user.

The weakness was shared by Jiva. The advisory is available at jivasecurity.com. This vulnerability was named CVE-2026-40521 since 04/13/2026. The exploitation appears to be easy. The attack can be initiated remotely. Technical details are known, but there is no available exploit. This vulnerability is assigned to T1006 by the MITRE ATT&CK project.

Upgrading to version 2.4.20 eliminates this vulnerability. Applying the patch 701fea6848da4a02fb83d30f07a9c0473d6b7e33 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

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Productinfo

Type

• Accounting Software

Name

• FrontAccounting

Version

• 2.4.0
• 2.4.1
• 2.4.2
• 2.4.3
• 2.4.4
• 2.4.5
• 2.4.6
• 2.4.7
• 2.4.8
• 2.4.9
• 2.4.10
• 2.4.11
• 2.4.12
• 2.4.13
• 2.4.14
• 2.4.15
• 2.4.16
• 2.4.17
• 2.4.18
• 2.4.19

License

• open-source

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• 🔒
• 🔒

CPE 2.2info

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• 🔒
• 🔒

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