#VU93625 Resource management error in Linux kernel - CVE-2021-47109

Vulnerability identifier: #VU93625

Vulnerability risk: Medium

CVSSv4.0: 1.3 [CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-47109

CWE-ID: CWE-399

Exploitation vector: Local network

Exploit availability: No

Vulnerable software:
Linux kernel
Operating systems & Components / Operating system

Vendor: Linux Foundation

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to improper management of internal resources within the system when handling NUD_NOARP entries for IPv6. A remote attacker can fill up the neighbour table with enough entries that it will overflow for valid connections after that.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: All versions

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External links
https://git.kernel.org/stable/c/d99029e6aab62aef0a0251588b2867e77e83b137
https://git.kernel.org/stable/c/d17d47da59f726dc4c87caebda3a50333d7e2fd3
https://git.kernel.org/stable/c/ddf088d7aaaaacfc836104f2e632b29b1d383cfc
https://git.kernel.org/stable/c/7a6b1ab7475fd6478eeaf5c9d1163e7a18125c8f

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.