Riskcovery

CVE-2021-47109

neighbour: allow NUD_NOARP entries to be forced GCed

State
Published
Severity
7.5 High
Published
Mar 15, 2024
Updated
Aug 5, 2026
Reserved
Mar 4, 2024

Read the record on cve.org

Description

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

neighbour: allow NUD_NOARP entries to be forced GCed

IFF_POINTOPOINT interfaces use NUD_NOARP entries for IPv6. It's possible to fill up the neighbour table with enough entries that it will overflow for valid connections after that.

This behaviour is more prevalent after commit 58956317c8de ("neighbor: Improve garbage collection") is applied, as it prevents removal from entries that are not NUD_FAILED, unless they are more than 5s old.

Scores

CVSSScoreVectorSource
3.17.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HLinux

Weaknesses

The record names no weakness.

Affected Products

ProductVersions
LinuxLinux
  • 58956317c8de52009d1a38a721474c24aef74fe7 to before d99029e6aab62aef0a0251588b2867e77e83b137Affected
  • 58956317c8de52009d1a38a721474c24aef74fe7 to before d17d47da59f726dc4c87caebda3a50333d7e2fd3Affected
  • 58956317c8de52009d1a38a721474c24aef74fe7 to before ddf088d7aaaaacfc836104f2e632b29b1d383cfcAffected
  • 58956317c8de52009d1a38a721474c24aef74fe7 to before 7a6b1ab7475fd6478eeaf5c9d1163e7a18125c8fAffected
LinuxLinux
  • 5.0Affected
  • before 5.0Not affected
  • 5.4.125 through 5.4.*Not affected
  • 5.10.43 through 5.10.*Not affected
  • 5.12.10 through 5.12.*Not affected
  • 5.13 and laterNot affected

References

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