CVE-2026-40521 Details
Description
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.
A path traversal vulnerability has been identified in FrontAccounting versions prior to 2.4.20, specifically within the attachment upload handler. This vulnerability allows authenticated attackers to execute arbitrary code by uploading files that include traversal sequences in the 'unique_name' parameter. Exploitation involves sending a crafted file attachment that exploits the path traversal flaw to write a PHP web shell into the web root, which can then be executed on the server.
Users are advised to upgrade to FrontAccounting version 2.4.20 or later, where this vulnerability has been fixed.
Metrics
CVSS 4.0 Severity and Vector Strings:
VolerionCVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
Volerion
Assessed Jun 29, 2026CISA-ADP
Assessed Jun 30, 2026References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.
| URL | Source(s) | Tag(s) |
|---|---|---|
| https://github.com/FrontAccountingERP/FA/commit/701fea6848da4a02fb83d30f07a9c0473d6b7e33 | [email protected] | Source CodeVendor |
| https://jivasecurity.com/writeups/frontaccounting-rce-attachment-upload-cve-2026-40521 | [email protected] | ExploitRemedyTechnical Analysis |
| https://sourceforge.net/p/frontaccounting/news/2026/04/release-2420/ | [email protected] | Release NotesVendor |
| https://www.vulncheck.com/advisories/frontaccounting-path-traversal-rce-via-attachment-upload | [email protected] | AdvisoryRemedy |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-22 | Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| FrontAccounting | < 2.4.20 (semver) |
CPE
Remediation
| |
Change History
2 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Jun 30, 2026 | CVE Modified | CISA-ADP |
| Jun 29, 2026 | New CVE Received | [email protected] |