CVE-2021-47109
Last modified
CVE-2021-47109 is a medium-severity vulnerability rated 5.5/10 on the CVSS scale. 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.. EPSS estimates a 0.24% chance of exploitation in the next 30 days.
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.
Metrics
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions | Update |
|---|---|---|---|
| Linux | Linux Kernel | >= 5.0, < 5.4.125 | — |
| Linux | Linux Kernel | >= 5.5, < 5.10.43 | — |
| Linux | Linux Kernel | >= 5.11, < 5.12.10 | — |
| Linux | Linux Kernel | 5.13 | Rc1 |
References
Timeline
- Published
- Last Modified
- Status
- Modified
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