#VU48967 Use-after-free in Linux kernel - CVE-2020-27825

Vulnerability identifier: #VU48967

Vulnerability risk: Low

CVSSv4.0: 0.4 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2020-27825

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 compromise vulnerable system.

The vulnerability exists due to a use-after-free error in kernel/trace/ring_buffer.c in Linux kernel, when trace_open and resize of cpu buffer are running in parallel on different CPUs. A local user can run a specially crafted application and perform a denial of service attack or read contentsof kernel memory.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Linux kernel: before 5.10, 5.10

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External links
https://bugzilla.redhat.com/show_bug.cgi?id=1905155
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=bbeb97464eefc65f506084fd9f18f21653e01137

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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.