Security settings manipulation via missing nonce validation
Published May 27, 2026 · Updated May 27, 2026
CSRF in youtag Two-factor authentication 2.1 and earlier allows remote attackers to alter firewall and 2FA settings via a forged request. The ipv_save_changes function accepts administrator-setting fields and persists operating mode, request rules, authentication slug, and log-retention changes without correctly validating a request nonce. Exploitation requires an authenticated site administrator to submit the forged request; successful exploitation changes security configuration and can disable the plugin's protections.
Summary
What happened
CSRF in youtag Two-factor authentication 2.1 and earlier allows remote attackers to alter firewall and 2FA settings via a forged request. The ipv_save_changes function accepts administrator-setting fields and persists operating mode, request rules, authentication slug, and log-retention changes without correctly validating a request nonce. Exploitation requires an authenticated site administrator to submit the forged request; successful exploitation changes security configuration and can disable the plugin's protections.
The record
- CVE
- CVE-2026-8903
- Published
- May 27, 2026
- Updated
- May 27, 2026
- Vendor
- youtag
- Product
- Two-factor authentication (formerly IP Vault)
- Classifications
- CWE-352, T1562.001
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- May 27, 2026CVE publishedPublication date reported by the CVE source.
- May 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 <=2.1
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.
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