What is CVE-2026-34415?

CVE-2026-34415 is a critical-severity vulnerability in Thexerteproject Xerteonlinetoolkits, classified under Incomplete List of Disallowed Inputs. CVSS score: 9.8/10. Published 2026-04-22.

How severe is CVE-2026-34415?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Is CVE-2026-34415 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Vulnerability in Thexerteproject Xerteonlinetoolkits

CVE-2026-34415

Xerte Online Toolkits versions 3.15 and earlier contain an incomplete input validation vulnerability in the elFinder connector endpoint that fails to block PHP-executable extensions .php4 due to an incorrect regex pattern. Unauthenticated attackers can exploit this flaw combined with authentication bypass and path traversal vulnerabilities to upload malicious PHP code, rename it with a .php4 extension, and execute arbitrary operating system commands on the server.

Published 2026-04-22 · last modified 2026-07-14.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.044 (91.0th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 91st percentile — 91.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.036 · newest: 0.044 · change: +0.009

Affected products

Thexerteproject Xerteonlinetoolkits — versions 3.15.0, 3.14.0, 3.13.0

Weakness classification (CWE)

CWE-184 — Incomplete List of Disallowed Inputs

Public proof-of-concept exploits

rapid7/metasploit-framework

References

github.com/bootstrapbool/xerteonlinetoolkits-rce (technical-description, exploit)
xerte.org.uk/xertetoolkits_3.15_ChangeLog.html (release-notes)
xerte.org.uk/index.php/en/downloads-1/category/3-xerte-online-toolkits (product, permissions-required)
github.com/thexerteproject/xerteonlinetoolkits/issues/1527 (issue-tracking)
github.com/thexerteproject/xerteonlinetoolkits/commit/02661be88cc369325ea01b508… (patch)
github.com/thexerteproject/xerteonlinetoolkits/commit/17e4f945fe6a3400fa88c01ed… (patch)
github.com/thexerteproject/xerteonlinetoolkits/commit/507d55c5e91bf9310b5b1c7fa… (patch)
www.vulncheck.com/advisories/xerte-online-toolkits-file-upload-rce-via-elfinder… (third-party-advisory)

Frequently asked questions

What is CVE-2026-34415?: CVE-2026-34415 is a critical-severity vulnerability in Thexerteproject Xerteonlinetoolkits, classified under Incomplete List of Disallowed Inputs. CVSS score: 9.8/10. Published 2026-04-22.
How severe is CVE-2026-34415?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2026-34415 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.