🛡️ CVE-2026-40521

🟠 CVSS 8.8 — High ✅ No Known Exploit CWE-22 NVD
8.8
CVSS Score
0 Low4 Medium7 High9 Critical10

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.

How this vulnerability can be exploited

This issue can be reached over the network, attack complexity is low, an attacker needs low-level privileges on the target. No user interaction is required. The scope is unchanged, so the impact stays within the vulnerable component. Rated impact: confidentiality high, integrity high, availability high.

Weakness class

CVE-2026-40521 is classified as CWE-22: Path Traversal. A file path built from user input is not confined to the intended directory, letting an attacker reach files elsewhere on the filesystem.

Affected software

CVE-2026-40521 is recorded against 1 package.

  • unknown

Timeline and source

Published on 29 June 2026 and last revised on 30 June 2026. No public exploit is currently recorded for this entry. Record sourced from NVD.

References

github.com
jivasecurity.com
sourceforge.net
www.vulncheck.com

Details

Severity HIGH
CVSS Score 8.8
CVSS Vector CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE CWE-22
Public Exploit ✅ No
Source NVD
Published 2026-06-29
Updated 2026-08-11
Modified 2026-06-30
Fix URL N/A

Affected Packages

Software From version Fixed in
unknown — —

Similar Threats

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