Privilege escalation in Linux kernel

1) Use-after-free

EUVDB-ID: #VU27503

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-2019-19768

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 in the __blk_add_trace() function in kernel/trace/blktrace.c. A local user can run a specially crafted program, trigger a use-after-free error and execute arbitrary code on the system with elevated privileges.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Linux kernel: 4.18 - 5.5.7

CPE2.3

• cpe:2.3:o:linux_foundation:linux_kernel:4.18:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.18.1:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.18.2:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.18.3:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.18.4:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.18.5:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.18.6:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.18.7:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.18.8:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.18.9:*:*:*:*:*:*:*

External links

https://lists.opensuse.org/opensuse-security-announce/2020-03/msg00039.html
https://bugzilla.kernel.org/show_bug.cgi?id=205711
https://security.netapp.com/advisory/ntap-20200103-0001/
https://usn.ubuntu.com/4344-1/

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.