Privilege escalation in Linux kernel tun

1) Double Free

EUVDB-ID: #VU89391

Risk: Low

CVSSv3.1: 6.8 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-47082

CWE-ID: CWE-415 - Double Free

Exploit availability: No

Description

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

The vulnerability exists due to a boundary error in drivers/net/tun.c. A local user can trigger a double free error and execute arbitrary code with elevated privileges.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Linux kernel: All versions

External links

http://git.kernel.org/stable/c/8eb43d635950e27c29f1e9e49a23b31637f37757
http://git.kernel.org/stable/c/0c0e566f0387490d16f166808c72e9c772027681
http://git.kernel.org/stable/c/a01a4e9f5dc93335c716fa4023b1901956e8c904
http://git.kernel.org/stable/c/3cb5ae77799e8ed6ec3fec0b6b4cd07f01650cc5
http://git.kernel.org/stable/c/158b515f703e75e7d68289bf4d98c664e1d632df

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.