Vulnerability identifier: #VU58332

Vulnerability risk: Low

CVSSv3.1:

CVE-ID: CVE-2020-36385

CWE-ID: CWE-416

Exploitation vector: Local

Exploit availability: No

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

Vendor:

Description

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

The vulnerability exists due to a use-after-free error in drivers/infiniband/core/ucma.c, because the ctx is reached via the ctx_list in some ucma_migrate_id situations where ucma_close is called. A local user can run a specially crafted program to trigger the use-after-free error and execute arbitrary code with elevated privileges.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

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External links
http://syzkaller.appspot.com/bug?id=457491c4672d7b52c1007db213d93e47c711fae6
http://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=f5449e74802c1112dea984aec8af7a33c4516af1
http://sites.google.com/view/syzscope/kasan-use-after-free-read-in-ucma_close-2
http://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10

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Q & A

Can this vulnerability be exploited remotely?

Is there known malware, which exploits this vulnerability?