CVE-2026-11907: Stream <= 4.2.0 - Missing Authorization to Authenticated (Subscriber+) Sensitive Information Disclosure via Heartbeat API

Is it exploited?

Reported, not confirmed by CISA. VulnCheck KEV lists it as exploited in the wild. CISA has not added it to its Known Exploited Vulnerabilities catalog as of 29 Oct 2026.

VulnCheck KEV lists it since 11 Aug 2026. It cites 1 public report, the first from 11 Aug 2026.

• patchstack.com

How likely is exploitation in the next 30 days?

0.4%

EPSS score, percentile 31.5 of all scored records. A probability estimated by FIRST, not a report of exploitation.

How severe?

6.5 Medium

CVSS v3.1 base score, given by the CNA

What should I do?

CISA has set no required action, because the vulnerability is not in KEV.

The CVE record links no vendor advisory, patch or mitigation.

Which versions are affected?

Affected

• 4.2.0 and earlier

Versions by product

Source: CISA KEV 2026.10.29, as of 29 Oct 2026; VulnCheck KEV, as of 30 Oct 2026; FIRST EPSS, as of 29 Oct 2026; CVE List, as of 30 Oct 2026. About the data.

Description

Stream <= 4.2.0 - Missing Authorization to Authenticated (Subscriber+) Sensitive Information Disclosure via Heartbeat API

The Stream plugin for WordPress is vulnerable to authorization bypass in all versions up to, and including, 4.2.0. This is due to the plugin not properly verifying that a user is authorized to perform an action. This makes it possible for authenticated attackers, with subscriber-level access and above, to access all Stream activity records via the Heartbeat API.

Source: CVE List, as of 30 Oct 2026. About the data.

What to do

Advisories and patches

The CVE record links no vendor advisory, patch or mitigation.

This summary is based on the CVE record as of 30 Oct 2026. Check the vendor's advisory before you act: affected versions and fixes can change.

Affected products and versions

Source: CVE List, as of 30 Oct 2026. About the data.

Timeline