Use-after-free in Linux kernel

1) Use-after-free

EUVDB-ID: #VU28416

Risk: Low

CVSSv4.0: 4.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2020-8648

CWE-ID: CWE-416 - Use After Free

Exploit availability: No

Description

The vulnerability allows a local authenticated user to #BASIC_IMPACT#.

There is a use-after-free vulnerability in the Linux kernel through 5.5.2 in the n_tty_receive_buf_common function in drivers/tty/n_tty.c.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Linux kernel: 4.4 - 5.5.19

CPE2.3

• cpe:2.3:o:linux_foundation:linux_kernel:4.4:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.4.0:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.4.0-57:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.4.1:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.4.2:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.4.3:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.4.4:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.4.5:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.4.6:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.4.7:*:*:*:*:*:*:*

External links

https://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.4.216
https://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.9.216
https://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.109
https://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.173
https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.5.9
https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.4.25
https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.6

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.