CVE-2026-3906

CVE-2026-3906 is a medium-severity vulnerability with a CVSS 3.x base score of 4.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-862.

Key facts

Description

WordPress core is vulnerable to unauthorized access in versions 6.9 through 6.9.1. The Notes feature (block-level collaboration annotations) was introduced in WordPress 6.9 to allow editorial comments directly on posts in the block editor. However, the REST API `create_item_permissions_check()` method in the comments controller did not verify that the authenticated user has `edit_post` permission on the target post when creating a note. This makes it possible for authenticated attackers with Subscriber-level access to create notes on any post, including posts authored by other users, private posts, and posts in any status.

Frequently asked questions

What is CVE-2026-3906?
WordPress core is vulnerable to unauthorized access in versions 6.9 through 6.9.1. The Notes feature (block-level collaboration annotations) was introduced in WordPress 6.9 to allow editorial comments directly on posts in the block editor. However, the REST API `create_item_permissions_check()` method in the comments controller did not verify that the authenticated user has `edit_post` permission on the target post when creating a note. This makes it possible for authenticated attackers with Subscriber-level access to create notes on any post, including posts authored by other users, private posts, and posts in any status.
How severe is CVE-2026-3906?
CVE-2026-3906 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2026-3906 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (22nd percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-3906?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-3906 have an EU (EUVD) identifier?
Yes. CVE-2026-3906 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-11134.
When was CVE-2026-3906 published?
CVE-2026-3906 was published on 2026-03-11 and last updated on 2026-06-17.

References

Other CWE-862 (Missing Authorization) vulnerabilities

Browse all CWE-862 (Missing Authorization) vulnerabilities →