CRITICAL

CVE-2026-15341

CVSS v3

9.8

CRITICAL

EPSS Score

0.3%

exploit probability

CISA KEV

No

known exploited

Exploitation

SSVC status

Description

The User Session Synchronizer plugin for WordPress is vulnerable to Authentication Bypass leading to Account Takeover in all versions up to, and including, 1.4.0. The `synchronize_session()` function, hooked on `init` and therefore executed on every request, performs no nonce, capability, or shared-secret validation against the attacker-supplied `ussync-key`, `ussync-token`, and `ussync-ref` parameters; when `ussync-key` references an unregistered slot, `get_option()` returns `false` for both th

Technical details

CVSS v3 Vector
3.1
Published
8/15/2026
Last Modified
8/15/2026

Frequently asked questions

What is CVE-2026-15341?

The User Session Synchronizer plugin for WordPress is vulnerable to Authentication Bypass leading to Account Takeover in all versions up to, and including, 1.4.0. The `synchronize_session()` function, hooked on `init` and therefore executed on every request, performs no nonce, capability, or shared-secret validation against the attacker-supplied `ussync-key`, `ussync-token`, and `ussync-ref` parameters; when `ussync-key` references an unregistered slot, `get_option()` returns `false` for both th

Is CVE-2026-15341 actively exploited?

Active exploitation of CVE-2026-15341 has not been confirmed. The EPSS score is 0.3%, indicating the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2026-15341?

CVE-2026-15341 has a CVSS v3 base score of 9.8 (CRITICAL severity), with vector string 3.1.

Is CVE-2026-15341 affecting your environment?

Use isMalicious to check if any of your IPs or domains are associated with this vulnerability's IOCs.