WordPress WordPress Core Time-of-check Time-of-use (TOCTOU) Race Condition Vulnerability

WordPress WordPress Core contains a time-of-check time-of-use (TOCTOU) race condition vulnerability that could allow unauthenticated attackers to execute code on the server during the upgrade window. This is due to predictable, web-accessible staging paths used during full-package core upgrades.

Why it matters

• This vulnerability is listed in CISA's Known Exploited Vulnerabilities catalog, which means it has been observed being exploited in the wild.

Affected

• Vendor: WordPress
• Product: WordPress Core
• Identifier: CVE-2026-119977
• FlawFind severity: high
• Weakness: CWE-367

What to do

• Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
• U.S. federal remediation deadline: 2026-11-06
• Inventory the affected product, prioritise internet-facing instances, and patch or mitigate immediately.
• Audit your own systems for the same weakness class — FlawFind can test your applications and APIs for it and prove what is exploitable.

Notes

https://wordpress.org/news/2026/10/wordpress-7-1-4 ; https://www.wordfence.com/threat-intel/vulnerabilities/wordpress-core/wordpress-core-470-713-unauthenticated-upgrade-window-staged-installer-remote-code-execution ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2026-119977