CVE-2026-39455 BIG-IP Configuration utility vulnerability
Attackers can exhaust file descriptors in the httpd process via LDAP authentication, causing a denial of service on BIG-IP devices.
- 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-2026-39455?
CVE-2026-39455 is a high-severity denial of service vulnerability in F5 Big-Ip Access Policy Manager, published on 13 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
When the BIG-IP Configuration utility is configured to use Lightweight Directory Access Protocol (LDAP) authentication, undisclosed traffic can cause the httpd process to exhaust the available file descriptors. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
Weakness: CWE-772
Which versions are affected by CVE-2026-39455?
It affects 21 products.
Products include F5 Big-Ip Access Policy Manager, F5 Big-Ip Advanced Firewall Manager, F5 Big-Ip Advanced Web Application Firewall, F5 Big-Ip Analytics, F5 Big-Ip Application Acceleration Manager, F5 Big-Ip Application Security Manager and 15 more.
How do I fix CVE-2026-39455?
No fix has been published for CVE-2026-39455 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-39455 being exploited?
There is no known exploitation of CVE-2026-39455 in the wild and no public exploit code.
Other vulnerabilities in F5 Big-Ip Access Policy Manager
- CVE-2023-46747 F5 BIG-IP Configuration Utility Authentication Bypass
- CVE-2022-1388 F5 BIG-IP Missing Authentication
- CVE-2021-22986 F5 BIG-IP and BIG-IQ Centralized Management iControl REST Remote Code Execution
- CVE-2021-22991 F5 BIG-IP Traffic Management Microkernel Buffer Overflow
- CVE-2020-5902 F5 BIG-IP Traffic Management User Interface (TMUI) Remote Code Execution
Sources
Also known as GHSA-6225-9whv-x529.