CVE-2026-23139 PUBLISHED

netfilter: nf_conncount: update last_gc only when GC has been performed

Assigner: Linux
Reserved: 13.01.2026 Published: 14.02.2026 Updated: 14.02.2026

In the Linux kernel, the following vulnerability has been resolved:

netfilter: nf_conncount: update last_gc only when GC has been performed

Currently last_gc is being updated everytime a new connection is tracked, that means that it is updated even if a GC wasn't performed. With a sufficiently high packet rate, it is possible to always bypass the GC, causing the list to grow infinitely.

Update the last_gc value only when a GC has been actually performed.

Product Status

Vendor Linux
Product Linux
Versions Default: unaffected
  • affected from f106694733c66a48740c25bc4e212e9b2ea364ce to 2c7c71113ed6d3e2f3aca4c088f22283016ff34f (excl.)
  • affected from be69850b461e7b491d87a22e33ab76fdd04b725e to c4cde57c8affdcca5bcff53a1047e15d268bdca1 (excl.)
  • affected from d265929930e2ffafc744c0ae05fb70acd53be1ee to 9f45588993d7f115280fc726119ca86fba32a811 (excl.)
  • affected from d265929930e2ffafc744c0ae05fb70acd53be1ee to 3cd717359e56f82f06cbf8279b47a7d79880c6f3 (excl.)
  • affected from d265929930e2ffafc744c0ae05fb70acd53be1ee to 26a82dce2beee39c43c109d9647e16f49cb02a35 (excl.)
  • affected from d265929930e2ffafc744c0ae05fb70acd53be1ee to 8bdafdf4900040a81422056cabe5e00a37bd101a (excl.)
  • affected from d265929930e2ffafc744c0ae05fb70acd53be1ee to 7811ba452402d58628e68faedf38745b3d485e3c (excl.)
Vendor Linux
Product Linux
Versions Default: affected
  • Version 5.19 is affected
  • unaffected from 0 to 5.19 (excl.)
  • unaffected from 6.1.161 to 6.1.* (incl.)
  • unaffected from 6.6.121 to 6.6.* (incl.)
  • unaffected from 6.12.66 to 6.12.* (incl.)
  • unaffected from 6.18.6 to 6.18.* (incl.)
  • unaffected from 6.19 to * (incl.)

References