Privilege escalation in Linux kernel

1) Use-after-free

EUVDB-ID: #VU24711

Risk: Low

CVSSv3.1: 7.7 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-7053

CWE-ID: CWE-416 - Use After Free

Exploit availability: No

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 - 5.1.21

External links

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

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.