CVE-2026-40521

HIGHPre-NVD 8.88.8—
EchelonGraph scoreHIGH confidence

Score 8.8 from GitHub Security Advisory (severity: HIGH) published 2026-06-29. a secondary CVSS source baseline 8.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 3 sources updated this week
8.8
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 1%CVSS: 8.8Exploit: NoneExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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 v3
8.8
EG Score
8.8(high)
EPSS
45.7%
KEV
Not listed

Published

June 29, 2026

Last Modified

June 30, 2026

Advisory Details (4)

Auto-updated Jun 29, 2026
Upstream fix merged — awaiting tagged release. Sources: github_commit.
generic

FrontAccounting < 2.4.20 Path Traversal RCE via attachment upload | Advisories | VulnCheck

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

FrontAccounting / News: Release 2.4.20

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

FrontAccounting RCE: When htmlspecialchars Meets Path Traversal — Jiva Security

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

commit 701fea6848da (FrontAccountingERP/FA)

Fix landed in FrontAccountingERP/FA commit 701fea6848da — awaiting tagged release

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

Vendor Advisories for CVE-2026-40521(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 34× in last 7d / 38× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-07-07 05:37 UTCEG score recompute
  2. 2026-07-07 05:36 UTCGHSA enrichment
  3. 2026-07-06 16:28 UTCEG score recompute
  4. 2026-07-06 16:28 UTCGHSA enrichment
  5. 2026-07-06 16:27 UTCEPSS rescore
  6. 2026-07-06 16:27 UTCEPSS rescore
  7. 2026-07-06 03:14 UTCEG score recompute
  8. 2026-07-06 03:14 UTCGHSA enrichment
  9. 2026-07-06 02:23 UTCEPSS rescore
  10. 2026-07-06 02:23 UTCEPSS rescore
  11. 2026-07-05 14:05 UTCEG score recompute
  12. 2026-07-05 14:05 UTCGHSA enrichment
  13. 2026-07-05 02:30 UTCEPSS rescore
  14. 2026-07-05 00:53 UTCEG score recompute
  15. 2026-07-05 00:53 UTCGHSA enrichment
  16. 2026-07-04 11:46 UTCEG score recompute
  17. 2026-07-04 11:46 UTCGHSA enrichment
  18. 2026-07-04 06:31 UTCEPSS rescore
  19. 2026-07-03 22:37 UTCEG score recompute
  20. 2026-07-03 22:37 UTCGHSA enrichment
  21. 2026-07-03 09:29 UTCEG score recompute
  22. 2026-07-03 09:29 UTCGHSA enrichment
  23. 2026-07-02 20:21 UTCEG score recompute
  24. 2026-07-02 20:21 UTCGHSA enrichment
  25. 2026-07-02 07:13 UTCEG score recompute
Show 13 more
  1. 2026-07-02 07:13 UTCGHSA enrichment
  2. 2026-07-01 18:06 UTCEG score recompute
  3. 2026-07-01 18:06 UTCGHSA enrichment
  4. 2026-07-01 15:06 UTCEPSS rescore
  5. 2026-07-01 04:59 UTCEG score recompute
  6. 2026-07-01 04:59 UTCGHSA enrichment
  7. 2026-06-30 23:22 UTCEPSS rescore
  8. 2026-06-30 15:49 UTCEG score recompute
  9. 2026-06-30 15:48 UTCGHSA enrichment
  10. 2026-06-30 02:40 UTCEG score recompute
  11. 2026-06-30 02:40 UTCGHSA enrichment
  12. 2026-06-29 13:33 UTCEG score recompute
  13. 2026-06-29 13:32 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-40521?
CVE-2026-40521 is a high vulnerability published on June 29, 2026. 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…
When was CVE-2026-40521 disclosed?
CVE-2026-40521 was first published in the National Vulnerability Database on June 29, 2026, with the most recent update on June 30, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-40521 actively exploited?
CVE-2026-40521 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 45.7% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-40521?
CVE-2026-40521 has a CVSS v3 base score of 8.8 (NVD).
How do I remediate CVE-2026-40521?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-40521, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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