CVE-2026-34964 Adminer before 5.5.0 SSRF via PDO DSN Injection
Attackers can bypass port restrictions to perform server-side request forgery against internal hosts via the login form.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-34964?
CVE-2026-34964 is a medium-severity server-side request forgery vulnerability in vrana adminer, published on 25 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Adminer before 5.5.0 contains a server-side request forgery vulnerability in the login form's server field validator, which only inspects leading integers for privileged ports and fails to reject non-numeric port values. Attackers can inject PDO DSN keys like host= and port= into the server parameter to bypass the privileged-port restriction and establish TCP connections to arbitrary internal hosts and ports before authentication.
Weakness: CWE-918
Which versions are affected by CVE-2026-34964?
How do I fix CVE-2026-34964?
Upgrade to a fixed version.
Upgrade, and send outbound requests through an allow-list that blocks internal addresses. More about Server-side request forgery.
Is CVE-2026-34964 being exploited?
There is no known exploitation of CVE-2026-34964 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-34964, GHSA-58cq-mgw2-38m5, GHSA-5v92-397q-w6q6, UBUNTU-CVE-2026-34964.