CVE-2026-40521

high

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.

References

https://www.vulncheck.com/advisories/frontaccounting-path-traversal-rce-via-attachment-upload

https://sourceforge.net/p/frontaccounting/news/2026/04/release-2420/

https://jivasecurity.com/writeups/frontaccounting-rce-attachment-upload-cve-2026-40521

https://github.com/FrontAccountingERP/FA/commit/701fea6848da4a02fb83d30f07a9c0473d6b7e33

Details

Source: Mitre, NVD

Published: 2026-06-29

Updated: 2026-06-30

Risk Information

CVSS v2

Base Score: 9

Vector: CVSS2#AV:N/AC:L/Au:S/C:C/I:C/A:C

Severity: High

CVSS v3

Base Score: 8.8

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Severity: High

CVSS v4

Base Score: 8.7

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Severity: High

EPSS

EPSS: 0.00627