CVE-2026-10821

Published Sep 2, 2026

Last updated 2 months ago

CVSS medium 6.6
Yoast

Overview

Description
The Yoast SEO Premium WordPress plugin before 27.6.1 does not sanitize control characters from redirect origins before writing them to the site's Apache configuration file when the file-based redirect mode is enabled, and the redirect-creation endpoint is reachable by users with only Author-level access. This allows such users to inject arbitrary newline-delimited Apache directives into the root .htaccess file. On Apache servers that honour PHP directives, the injection can be chained with the user's own media upload (a polyglot image carrying a PHP payload) and an auto_prepend_file directive to achieve Remote Code Execution.
Source
contact@wpscan.com
NVD status
Deferred

Risk scores

CVSS 3.1

Type
Secondary
Base score
6.6
Impact score
5.9
Exploitability score
0.7
Vector string
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
Severity
MEDIUM

Weaknesses

134c704f-9b21-4f2e-91b3-4a467353bcc0
CWE-74

Social media

Hype score
Not currently trending

Related CVEs

  1. The Yoast SEO – Advanced SEO with real-time guidance and built-in AI plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Post Slug (post_name) in all versions up to, and including, 28.0 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with author-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This requires pretty permalinks to be enabled, as the exploit chain depends on get_permalink() embedding the stored percent-encoded post_name in the generated URL.•CVE-2026-15425
  2. Yoast Duplicate Post through 4.6 contains a cross-site request forgery vulnerability in the duplicate_post_dismiss_notice handler, which verifies no nonce or capability. Attackers can trick any authenticated user into sending a request that sets the duplicate_post_show_notice site option, suppressing admin notices network-wide.•CVE-2026-53739
  3. Yoast Duplicate Post through 4.6 inserts an unescaped post title and permalink into the Classic Editor scheduled republish notice. Attackers can schedule a republish copy with a crafted title to execute script when an administrator views the resulting notice.•CVE-2026-53740
  4. The Yoast SEO plugin for WordPress is vulnerable to Insecure Direct Object References in all versions up to, and including, 26.5. This is due to insufficient authorization checks in the Meta Search REST API endpoint that fail to verify post ownership. This makes it possible for authenticated attackers, with Contributor-level access and above, to read sensitive SEO metadata from any post on the site via the 'post_id' parameter, including posts owned by other users, private posts, and draft posts.•CVE-2025-14481
  5. Heap-based Buffer Overflow vulnerability in mod_proxy_ajp of Apache HTTP Server. If mod_proxy_ajp connects to a malicious AJP server this AJP server can send a malicious AJP message back to mod_proxy_ajp and cause it to write 4 attacker controlled bytes after the end of a heap based buffer. This issue affects Apache HTTP Server: through 2.4.66. Users are recommended to upgrade to version 2.4.67, which fixes the issue.•CVE-2026-28780

References

Sources include official advisories and independent security research.