#VU63653 Use-after-free in Linux kernel - CVE-2020-25671

Vulnerability identifier: #VU63653

Vulnerability risk: Low

CVSSv4.0: 5.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2020-25671

CWE-ID: CWE-416

Exploitation vector: Local

Exploit availability: No

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

Vendor: Linux Foundation

Description

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a use-after-free error in the NFC LLCP protocol implementation. A local user can trigger the llcp_sock_connect() function to crash or escalate their privileges on the system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Linux kernel: before 5.11.14, 5.11.14

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External links
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/PW3OASG7OEMHANDWBM5US5WKTOC76KMH/
https://www.openwall.com/lists/oss-security/2020/11/01/1
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/UTVACC6PGS6OSD3EYY7FZUAZT2EUMFH5/
https://www.openwall.com/lists/oss-security/2020/11/01/1
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/VEIEGQXUW37YHZ5MTAZTDCIMHUN26NJS/
https://lists.debian.org/debian-lts-announce/2021/06/msg00019.html
https://lists.debian.org/debian-lts-announce/2021/06/msg00020.html
https://security.netapp.com/advisory/ntap-20210702-0008/

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

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