Unauthenticated administrator session hijacking via passwordless site registration
Published Jul 27, 2026 · Updated Jul 27, 2026
Authentication bypass in MainWP Child before 6.1.2 allows remote attackers to obtain an administrator session through site registration. The registration handler accepts a supplied login and public key without verifying identity when password authentication is disabled, then issues session cookies for that user. Exploitation requires an unconnected child with no effective Unique Security ID and a known login, but grants that account's WordPress privileges.
Summary
What happened
Authentication bypass in MainWP Child before 6.1.2 allows remote attackers to obtain an administrator session through site registration. The registration handler accepts a supplied login and public key without verifying identity when password authentication is disabled, then issues session cookies for that user. Exploitation requires an unconnected child with no effective Unique Security ID and a known login, but grants that account's WordPress privileges.
The record
- CVE
- CVE-2026-12255
- Published
- Jul 27, 2026
- Updated
- Jul 27, 2026
- Vendor
- MainWP
- Product
- MainWP Child
- Classifications
- CWE-287, T1078
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 27, 2026CVE publishedPublication date reported by the CVE source.
- Jul 27, 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 <6.1.2
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.
Public exploit references
- WPScan passwordless site-registration proof of conceptfunctional · validated
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