Quick Page/Post Redirect Plugin up to 5.2.3 on WordPress Update Checker backdoor

Summaryinfo

A vulnerability marked as critical has been reported in Quick Page and Post Redirect Plugin up to 5.2.3. The affected element is an unknown function of the file page_post_redirect_Quick Page/Post Redirect Plugin WordPress plugin before 5.2.4.php of the component Update Checker. The manipulation leads to backdoor. This vulnerability is traded as CVE-2026-126697. It is possible to initiate the attack remotely. There is no exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Quick Page and Post Redirect Plugin up to 5.2.3. It has been rated as critical. This issue affects an unknown code of the file page_post_redirect_Quick Page/Post Redirect Plugin WordPress plugin before 5.2.4.php of the component Update Checker. The manipulation with an unknown input leads to a backdoor vulnerability. Using CWE to declare the problem leads to CWE-912. The product contains functionality that is not documented, not part of the specification, and not accessible through an interface or command sequence that is obvious to the product's users or administrators. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

The Quick Page/Post Redirect Plugin WordPress plugin before 5.2.4 was distributed with a hidden update mechanism that fetched Quick Page/Post Redirect Plugin WordPress plugin before 5.2.4 updates from its author's own server instead of WordPress.org, which was used to push a backdoored build to sites, allowing the attacker controlling that server to inject arbitrary content into pages and to deliver arbitrary code to affected sites. Version 5.2.1, as published on WordPress.org, bundled the Quick Page/Post Redirect Plugin WordPress plugin before 5.2.4 Update Checker library (updater/ directory) configured to poll https://anadnet.com/updates/?action=get_metadata&slug=quick-pagepost-redirect-Quick Page/Post Redirect Plugin WordPress plugin before 5.2.4. In March 2021 that server delivered a modified 5.2.3 build, different from the 5.2.3 later published on WordPress.org, which kept the update channel and added a the_content filter that, for logged-out visitors on single posts and pages, fetched content from https://w.anadnet.com/bro/3/ (passing the site host, request URI and visitor User-Agent) and prepended the response to the post (observed serving SEO spam links to search engine crawlers). Because the version string matched a later WordPress.org release, affected sites were not offered a clean update until 5.2.4. Indicators of compromise: - Outbound requests to anadnet.com or w.anadnet.com - An updater/ directory (Quick Page/Post Redirect Plugin WordPress plugin before 5.2.4 Update Checker, Puc v4p10) inside wp-content/Quick Page/Post Redirect Plugin WordPress plugin before 5.2.4/quick-pagepost-redirect-Quick Page/Post Redirect Plugin WordPress plugin before 5.2.4/ - The strings filter_the_content_in_the_main_loop, ppr_pro, QQQEND or w.anadnet.com in page_post_redirect_Quick Page/Post Redirect Plugin WordPress plugin before 5.2.4.php - page_post_redirect_Quick Page/Post Redirect Plugin WordPress plugin before 5.2.4.php with MD5 ad717da18cf8a2b69899c0d7dafee05a (tampered 5.2.3) Remediation: remove the Quick Page/Post Redirect Plugin WordPress plugin before 5.2.4 (it has been closed on WordPress.org), or at minimum reinstall the clean 5.2.4 from WordPress.org, delete any leftover updater/ directory, verify the files with "wp Quick Page/Post Redirect Plugin WordPress plugin before 5.2.4 verify-checksums quick-pagepost-redirect-Quick Page/Post Redirect Plugin WordPress plugin before 5.2.4", clear the opcode cache, and treat any site that ran the tampered build as potentially compromised.

It is possible to read the advisory at wpscan.com. The identification of this vulnerability is CVE-2026-126697 since 11/11/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1588.001 according to MITRE ATT&CK.

By approaching the search of inurl:page_post_redirect_Quick Page/Post Redirect Plugin WordPress plugin before 5.2.4.php it is possible to find vulnerable targets with Google Hacking.

Upgrading to version 5.2.4 eliminates this vulnerability.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

• WordPress Plugin

Name

• Post Redirect Plugin
• Quick Page

Version

• 5.2.0
• 5.2.1
• 5.2.2
• 5.2.3

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CPE 2.2info

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