#VU91491 Race condition in Linux kernel - CVE-2020-29369

Vulnerability identifier: #VU91491

Vulnerability risk: Low

CVSSv4.0: 4.4 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2020-29369

CWE-ID: CWE-362

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 execute arbitrary code.

The vulnerability exists due to a race condition within the unmap_region(), detach_vmas_to_be_unmapped() and __do_munmap() functions in mm/mmap.c. A local user can execute arbitrary code.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: All versions

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External links
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=246c320a8cfe0b11d81a4af38fa9985ef0cc9a4c
https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.7.11
https://bugs.chromium.org/p/project-zero/issues/detail?id=2056
https://security.netapp.com/advisory/ntap-20210115-0001/
https://www.openwall.com/lists/oss-security/2021/02/10/6
https://www.openwall.com/lists/oss-security/2021/02/19/8

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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.