CVE-2021-47109

Summary

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.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux58956317c8de52009d1a38a721474c24aef74fe7 < d99029e6aab62aef0a0251588b2867e77e83b137affected
LinuxLinux58956317c8de52009d1a38a721474c24aef74fe7 < d17d47da59f726dc4c87caebda3a50333d7e2fd3affected
LinuxLinux58956317c8de52009d1a38a721474c24aef74fe7 < ddf088d7aaaaacfc836104f2e632b29b1d383cfcaffected
LinuxLinux58956317c8de52009d1a38a721474c24aef74fe7 < 7a6b1ab7475fd6478eeaf5c9d1163e7a18125c8faffected
LinuxLinux5.0affected
LinuxLinux0 < 5.0unaffected
LinuxLinux5.4.125 <= 5.4.*unaffected
LinuxLinux5.10.43 <= 5.10.*unaffected
LinuxLinux5.12.10 <= 5.12.*unaffected
LinuxLinux5.13 <= *unaffected

Weaknesses

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

CVE Program Container

Additional References

References