#VU24711 Use-after-free in Linux kernel - CVE-2020-7053

Vulnerability identifier: #VU24711

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-2020-7053

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 within the i915_ppgtt_close() function in drivers/gpu/drm/i915/i915_gem_gtt.c, related to i915_gem_context_destroy_ioctl() call in drivers/gpu/drm/i915/i915_gem_context.c. A local user can run a specially crafted application to execute arbitrary code on the system with elevated privileges.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Linux kernel: 4.4.0 - 4.4.165, 4.19 - 4.19.95, 5.0.0 - 5.0.21, 5.1.1 - 5.1.21

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External links
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1859522
https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.2
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=7dc40713618c884bf07c030d1ab1f47a9dc1f310
https://lore.kernel.org/stable/20200114183937.12224-1-tyhicks@canonical.com

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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.