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CVE-2026-53740 Yoast CVE debrief

CVE-2026-53740 is a MEDIUM-severity vulnerability (CVSS Score: 5.1) in the Yoast Duplicate Post plugin for WordPress, affecting versions through 4.6. The vulnerability allows an attacker to inject an unescaped post title and permalink into the Classic Editor scheduled republish notice. By scheduling a republish copy with a crafted title, an attacker can execute a script when an administrator views the resulting notice. The vulnerability was published on [cve-org](https://www.cve.org/CVERecord?id=CVE-2026-53740) and detailed further on [nvd](https://nvd.nist.gov/vuln/detail/CVE-2026-53740).

Vendor
Yoast
Product
Yoast Duplicate Post
CVSS
MEDIUM 5.1
CISA KEV
Not listed in stored evidence
Original CVE published
2026-06-10
Original CVE updated
2026-06-11
Advisory published
2026-06-10
Advisory updated
2026-06-11

Who should care

Administrators and users of WordPress sites utilizing the Yoast Duplicate Post plugin through version 4.6 should prioritize updating to a patched version to mitigate this vulnerability.

Technical summary

The Yoast Duplicate Post plugin for WordPress inserts an unescaped post title and permalink into the Classic Editor scheduled republish notice. This allows attackers to schedule a republish copy with a crafted title to execute a script when an administrator views the resulting notice, enabling stored Cross-Site Scripting (XSS) attacks.

Defensive priority

High

Recommended defensive actions

  • Update the Yoast Duplicate Post plugin to a version beyond 4.6.
  • Review and sanitize all post titles and permalinks used in conjunction with the plugin.
  • Monitor for suspicious activity related to the Classic Editor scheduled republish notice.

Evidence notes

Evidence suggests that the vulnerability exists within the Yoast Duplicate Post plugin, specifically affecting versions through 4.6. [ref-4](https://wordpress.org/plugins/duplicate-post/) and [ref-5](https://www.vulncheck.com/advisories/yoast-duplicate-post-through-stored-cross-site-scripting-via-scheduled-republish-notice) provide additional context and details about the vulnerability.

Official resources

CVE-2026-53740 was published on 2026-06-10T22:17:02.367Z and modified on 2026-06-11T15:22:26.633Z.