Quick answers
- Is CVE-2026-34964 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-34964 being exploited in the wild.
- How severe is CVE-2026-34964?
- Medium severity, with a CVSS score of 5.8, published 25 August 2026.
- Which products and versions are affected?
- Adminer before 5.5.0.
- Is there a fix for CVE-2026-34964?
- A patch was published on 2026-08-25: version 5.5.0 released Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-34964 attacked?
- It is attacked over the network, in a web application.
- Am I affected by CVE-2026-34964?
- Check whether you run Adminer at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
The vulnerability is a server-side request forgery (SSRF) in Adminer's login form caused by improper validation of the server parameter before it is interpolated into a PDO DSN. The port-validation function (auth.inc.php:179) only rejects ports that begin with an integer in the privileged range (<1024), allowing non-numeric ports like "zzz;host=10.0.0.5;port=22" to pass validation. When this crafted value is used to build the PDO DSN (e.g., mysql.inc.php:180), the PDO driver parses the injected semicolon-delimited keys and applies the last-appearing host=/port= values, bypassing the validator's restrictions. An attacker can submit the login form pre-authentication with a malicious server parameter to establish TCP connections to arbitrary internal endpoints. The issue affects PDO_MySQL, PDO_DBLIB, PDO_SQLSRV, and PDO_OCI drivers; PostgreSQL is not affected due to quoting in its DSN handling. The vulnerability was fixed in version 5.5.0.
Affected products
- Adminer Adminer before 5.5.0
Timeline
- 2026-07-17: disclosed
- 2026-08-25: patched: version 5.5.0 released