Jetpack 12.0 - 16.1.2 - Authenticated (Administrator+) PHP Object Injection

2026-09-03 00:00
Anonymous

Strategic Overview

Status
Patched in 12.0.3
Affected Plugin
Jetpack – WP Security, Backup, Speed, & Growth
Affected Version
12.0 – 16.1.2 · 42 branches
CVSS
7.2High
Weakness type
CWE-502 · Deserialization of Untrusted Data
CVE
CVE pending
View all Jetpack – WP Security, Backup, Speed, & Growth vulnerabilities

At a glance

This record tracks a high-severity Deserialization of Untrusted Data vulnerability in the Jetpack WordPress plugin, affecting versions 12.0 – 16.1.2 · 42 branches. It carries a CVSS score of 7.2 (reachable over the network; low attack complexity; high confidentiality, integrity, availability impact). Exploitation requires an authenticated account at Administrator level or above. The issue is fixed in version 12.0.3; sites on affected versions should update now. Disclosed September 2026.

Vulnerability Overview

The Jetpack – WP Security, Backup, Speed, & Growth plugin for WordPress is vulnerable to PHP Object Injection in versions 12.0 through 16.1.2 via deserialization of untrusted post metadata in the Jetpack Import REST API. This makes it possible for authenticated attackers with the import capability, which is granted to administrators by default, to inject a PHP object. The direct impact is attacker-controlled object instantiation; confidentiality, integrity, and availability impact requires a compatible POP chain in Jetpack or another installed component.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no interaction from a victim user. A successful exploit has high impact on confidentiality, integrity, availability — full site compromise territory.

CWE-502: Deserialization of Untrusted Data

Reaching this weakness in Jetpack 12.0 – 16.1.2 · 42 branches takes an account at Administrator level or above. Deserialization of untrusted data means the application reconstructs objects from input a caller controls, letting the attacker choose which classes get instantiated and what their properties hold.

A workable chain turns deserialization into file writes, deletions or code execution, depending on what the loaded classes do in their magic methods. For Jetpack the fix is 12.0.3: builds 12.0 – 16.1.2 · 42 branches are affected, anything from 12.0.3 onward is not.

Remediation

Update to one of the following versions, or a newer patched version: 12.0.3, 12.1.3, 12.2.3, 12.3.2, 12.4.2, 12.5.2, 12.6.4, 12.7.3, 12.8.3, 12.9.5, 13.0.2, 13.1.5, 13.2.4, 13.3.3, 13.4.5, 13.5.2, 13.6.2, 13.7.2, 13.8.3, 13.9.2, 14.0.1, 14.1.1, 14.2.2, 14.3.1, 14.4.2, 14.5.1, 14.6.1, 14.7.1, 14.8.1, 14.9.2, 15.0.3, 15.1.2, 15.2.1, 15.3.2, 15.4.1, 15.5.1, 15.6.1, 15.7.2, 15.8.1, 15.9.2, 16.0.2, 16.1.3

How does WordSec protect against this?

An attacker needs Administrator access first, so the firewall sees the attempt as traffic from a logged-in account: WordSec's web application firewall inspects request payloads before WordPress loads them. Classes like this one can leave something behind, so the staged malware scanner is the second half: it looks for dropped files and modified code rather than for the request that created them. None of that substitutes for the fix: Jetpack 12.0.3 closes this, and updating the plugin is the step that ends it.

  • Firewall
  • Scanner
  • Alerts

External References

https://www.wordfence.com/threat-intel/vulnerabilities/id/72f4776f-5450-4022-92dd-47ddaa91a5cd

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