CVE-2026-45860
HighCVSS 7.5Exploitation Probability (EPSS)
Low risk48th percentile - higher than 48% of all known CVEs
Summary
A vulnerability in the Linux kernel's netfilter module has been resolved regarding the connection clean-up limit. Fixes have been implemented to increase the clean-up limit to 64 connections and optimize the process of collecting unused connections.
Risk Assessment
Organizations may face performance issues if the number of new connections exceeds 8 per jiffy, potentially leading to inefficient connection management.
Recommendation
It is recommended to update the Linux kernel to the latest version to benefit from the fixes and to monitor the number of active connections to avoid performance issues.
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Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_conncount: increase the connection clean up limit to 64 After the optimization to only perform one GC per jiffy, a new problem was introduced. If more than 8 new connections are tracked per jiffy the list won't be cleaned up fast enough possibly reaching the limit wrongly. In order to prevent this issue, only skip the GC if it was already triggered during the same jiffy and the increment is lower than the clean up limit. In addition, increase the clean up limit to 64 connections to avoid triggering GC too often and do more effective GCs. This has been tested using a HTTP server and several performance tools while having nft_connlimit/xt_connlimit or OVS limit configured. Output of slowhttptest + OVS limit at 52000 connections: slow HTTP test status on 340th second: initializing: 0 pending: 432 connected: 51998 error: 0 closed: 0 service available: YES