Improper locking in Linux kernel mptcp

1) Improper locking

EUVDB-ID: #VU92354

Risk: Low

CVSSv4.0: 4.3 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-47590

CWE-ID: CWE-667 - Improper Locking

Exploit availability: No

Description

The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to improper locking within the __mptcp_push_pending() function in net/mptcp/protocol.c. A local user can perform a denial of service (DoS) attack.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Linux kernel: 5.15 - 5.16 rc8

CPE2.3

• cpe:2.3:o:linux_foundation:linux_kernel:5.15:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:5.15:rc1:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:5.15:rc2:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:5.15:rc3:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:5.15:rc4:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:5.15:rc5:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:5.15:rc6:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:5.15:rc7:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:5.15.0:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:5.15.1:*:*:*:*:*:*:*

External links

https://git.kernel.org/stable/c/23311b92755ffa9087332d1bb8c71c0f6a10cc08
https://git.kernel.org/stable/c/3d79e3756ca90f7a6087b77b62c1d9c0801e0820
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.15.11
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.16

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.