CVE-2026-40521
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.98%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 4.0
- 8.7 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.98% probability · 62th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-22
- Source
- disclosure@vulncheck.com
EPSS 1.0% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://github.com/FrontAccountingERP/FA/commit/701fea6848da4a02fb83d30f07a9c0473d6b7e33
- https://jivasecurity.com/writeups/frontaccounting-rce-attachment-upload-cve-2026-40521
- https://sourceforge.net/p/frontaccounting/news/2026/04/release-2420/
- https://www.vulncheck.com/advisories/frontaccounting-path-traversal-rce-via-attachment-upload
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.