Memory Leak via Undisclosed DNS Queries in F5 BIG-IP & BIG-IP Next CNF
CVE-2025-59781 Published on October 15, 2025
BIG-IP DNS cache vulnerability
When DNS cache is configured on a BIG-IP or BIG-IP Next CNF virtual server, undisclosed DNS queries can cause an increase in memory resource utilization. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
Vulnerability Analysis
CVE-2025-59781 can be exploited with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality and integrity, and a high impact on availability.
Weakness Type
What is an Insufficient Cleanup Vulnerability?
The software does not properly "clean up" and remove temporary or supporting resources after they have been used.
CVE-2025-59781 has been classified to as an Insufficient Cleanup vulnerability or weakness.
Products Associated with CVE-2025-59781
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Affected Versions
F5 BIG-IP:- Version 17.5.0 and below * is unaffected.
- Version 17.1.0 and below 17.1.2.2 is affected.
- Version 16.1.0 and below 16.1.6 is affected.
- Version 15.1.0 and below 15.1.10.8 is affected.
- Version 2.0.0 and below * is unaffected.
- Version 1.1.0 and below * is affected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.