Auth bypass in Mailerpress – Newsletter, Email Marketing & Ai Automation
CVE-2026-18436
The MailPress plugin for WordPress is vulnerable to unauthorized access in versions up to, and including, 1.5.0 via the campaign revision-restore REST endpoint (POST /wp-json/mailpress/v1/campaign/<id>/restore-revision/<revision_id>). The route in the vulnerable range was registered without a permissionCallback, allowing the restoreRevision() handler to run for unauthenticated requests and overwrite a campaign's content_html with any prior revision. This makes it possible for unauthenticated attackers to modify campaign content by restoring an arbitrary revision.
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.
EPSS exploit prediction
EPSS: 0.004 (33.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 33rd percentile — 33.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-18436?
- CVE-2026-18436 is a medium-severity vulnerability in Mailerpress – Newsletter, Email Marketing & Ai Automation, classified under Missing Authorization. CVSS score: 5.3/10. Published 2026-07-31.
- How severe is CVE-2026-18436?
- Medium severity. CVSS v3 base score is 5.3 out of 10.