CVE-2026-16267: CWE-502 Deserialization of Untrusted Data in Newsletters
The Newsletters WordPress plugin before 4.16 does not restrict the classes allowed when unserialising a value taken from a public form submission, allowing unauthenticated attackers to inject arbitrary PHP objects.
AI Analysis
Technical Summary
CVE-2026-16267 is a deserialization of untrusted data vulnerability (CWE-502) in the Newsletters WordPress plugin versions prior to 4.16. The plugin does not restrict which PHP classes can be unserialized from user-supplied input submitted through a public form. This flaw allows unauthenticated attackers to inject arbitrary PHP objects, potentially leading to remote code execution or other high-impact consequences.
Potential Impact
Successful exploitation can lead to full compromise of the affected WordPress site, including confidentiality, integrity, and availability impacts. The CVSS score of 8.1 reflects high severity with network attack vector, high impact on confidentiality, integrity, and availability, and no privileges or user interaction required.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, avoid using affected versions or restrict access to the vulnerable functionality if possible.
CVE-2026-16267: CWE-502 Deserialization of Untrusted Data in Newsletters
Description
The Newsletters WordPress plugin before 4.16 does not restrict the classes allowed when unserialising a value taken from a public form submission, allowing unauthenticated attackers to inject arbitrary PHP objects.
CVSS v3.1
Score 8.1high
Affected software
Newsletters
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-16267 is a deserialization of untrusted data vulnerability (CWE-502) in the Newsletters WordPress plugin versions prior to 4.16. The plugin does not restrict which PHP classes can be unserialized from user-supplied input submitted through a public form. This flaw allows unauthenticated attackers to inject arbitrary PHP objects, potentially leading to remote code execution or other high-impact consequences.
Potential Impact
Successful exploitation can lead to full compromise of the affected WordPress site, including confidentiality, integrity, and availability impacts. The CVSS score of 8.1 reflects high severity with network attack vector, high impact on confidentiality, integrity, and availability, and no privileges or user interaction required.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, avoid using affected versions or restrict access to the vulnerable functionality if possible.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- WPScan
- Date Reserved
- 2026-07-20T09:09:37.520Z
- State
- PUBLISHED
Threat ID: 6a76cc2abf8831d539114703
Added to database: 08/08/2026, 06:26:50 UTC
Last enriched: 08/15/2026, 14:59:26 UTC
Last updated: 09/22/2026, 01:52:42 UTC
Views: 47
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