Unauthenticated service crash via unbounded POST iteration
Published May 4, 2026 · Updated May 4, 2026
Uncontrolled resource consumption in Jules Colle Conditional Fields for Contact Form 7 before 2.7.3 allows remote attackers to crash PHP processes. Wpcf7cfMailParser::hide_hidden_mail_fields_regex_callback() uses a repeater *_count POST value as a loop bound without validation, repeatedly invoking preg_replace(). An unauthenticated REST API submission can exhaust server memory and interrupt form processing and other PHP-backed requests in the affected process.
Summary
What happened
Uncontrolled resource consumption in Jules Colle Conditional Fields for Contact Form 7 before 2.7.3 allows remote attackers to crash PHP processes. Wpcf7cfMailParser::hide_hidden_mail_fields_regex_callback() uses a repeater *_count POST value as a loop bound without validation, repeatedly invoking preg_replace(). An unauthenticated REST API submission can exhaust server memory and interrupt form processing and other PHP-backed requests in the affected process.
The record
- CVE
- CVE-2026-25863
- Published
- May 4, 2026
- Updated
- May 4, 2026
- Vendor
- Jules Colle
- Product
- Conditional Fields for Contact Form 7
- Classifications
- CWE-1284, T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- May 4, 2026CVE publishedPublication date reported by the CVE source.
- May 4, 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 <2.7.3
What conditions does exploitation require?
What is affected?
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.
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
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo