#VU51547 Use-after-free in Linux kernel - CVE-2020-25656
Vulnerability identifier: #VU51547
Vulnerability risk: Low
CVSSv4.0: 4.3 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]
CVE-ID: CVE-2020-25656
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 gain access to sensitive information.
The vulnerability exists due to a use-after-free error in the way the console subsystem uses KDGKBSENT and KDSKBSENT IOCTLs. A local user can run a specially crafted program to trigger an out-of-bounds read and gain access to sensitive information.
Mitigation
Install updates from vendor's website.
Vulnerable software versions
Linux kernel: before 5.10, 5.10
External links
https://bugzilla.redhat.com/show_bug.cgi?id=1888726
https://lists.debian.org/debian-lts-announce/2020/12/msg00015.html
https://lists.debian.org/debian-lts-announce/2020/12/msg00027.html
https://lkml.org/lkml/2020/10/16/84
https://lkml.org/lkml/2020/10/29/528
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.
