CVE-2026-0686 Webmention <= 5.6.2 - Unauthenticated Blind Server-Side Request Forgery
Unauthenticated attackers can exploit a Server-Side Request Forgery flaw in the Webmention WordPress plugin to query and modify internal services.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-0686?
CVE-2026-0686 is a high-severity server-side request forgery vulnerability in pfefferle Webmention, published on 2 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
The Webmention plugin for WordPress is vulnerable to Server-Side Request Forgery in all versions up to, and including, 5.6.2 in the 'MF2::parse_authorpage' function via the 'Receiver::post' function. This makes it possible for unauthenticated attackers to make web requests to arbitrary locations originating from the web application and can be used to query and modify information from internal services.
Weakness: CWE-918
Which versions are affected by CVE-2026-0686?
How do I fix CVE-2026-0686?
No fix has been published for CVE-2026-0686 yet. Limit exposure of the affected software until one is available.
Upgrade, and send outbound requests through an allow-list that blocks internal addresses. More about Server-side request forgery.
Is CVE-2026-0686 being exploited?
There is no known exploitation of CVE-2026-0686 in the wild and no public exploit code.
Sources
Also known as GHSA-pwm7-wr54-2jxv.