Unauthenticated code execution via unchecked signature file uploads
Published Oct 10, 2026 · Updated Oct 10, 2026
File upload in HasThemes Extensions For CF7 3.4.5 and earlier allows remote attackers to execute code via signature-field submissions. The signature field's validation_filter() omits extension, MIME type, and size checks, while extcf7_submit accepts filenames that sanitize_file_name() converts from shell.php- to shell.php. Exploitation requires access to the signature upload path, and code execution depends on the server executing PHP files in the unguarded upload directory.
Summary
What happened
File upload in HasThemes Extensions For CF7 3.4.5 and earlier allows remote attackers to execute code via signature-field submissions. The signature field's validation_filter() omits extension, MIME type, and size checks, while extcf7_submit accepts filenames that sanitize_file_name() converts from shell.php- to shell.php. Exploitation requires access to the signature upload path, and code execution depends on the server executing PHP files in the unguarded upload directory.
The record
- CVE
- CVE-2026-94589
- Published
- Oct 10, 2026
- Updated
- Oct 10, 2026
- Vendor
- HasThemes
- Product
- Extensions For CF7
- Classifications
- CWE-434, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Oct 10, 2026CVE publishedPublication date reported by the CVE source.
- Oct 10, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0 <=3.4.5
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Activity data is delayed. The latest report is Sep 28, 2026.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Get started to see how Hinoki identifies affected software and validates exploitability in your environment.
Get started