CVE-2026-39455

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.

CVSS v3.1 Score

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS — Exploit Prediction

0.0011

Probability of exploitation

0.28%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-772 CWE-772

References

Other References

https://my.f5.com/manage/s/article/K000160874

Frequently Asked Questions

What is CVE-2026-39455? +

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. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2026-39455? +

CVE-2026-39455 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0011, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-39455? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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