PT-2021-8229 · Linux+3 · Linux Kernel+3

Florian Westphal · Published 2021-12-14 · Updated 2024-12-02 · CVE-2021-47593

Positive Technologies (AI Summary)

CVSS v3.1

5.5

Medium

Base vector

AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description The issue is related to the mptcp component of the Linux kernel, which can cause a crash due to a null pointer dereference. This occurs when the sk->sk sock kern flag is not set correctly, allowing setsockopt to work for plain TCP sockets. In the case of a fallback, accept() can return a plain TCP socket that is still tagged as 'kernel', leading to a crash. The subflow extension has a NULL ctx->conn mptcp socket, resulting in a null pointer dereference in subflow data ready.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

NULL Pointer Dereference

Weakness Enumeration

CWE-476

Related Identifiers

BDU:2024-11553

CVE-2021-47593

OPENSUSE-SU-2024_2947-1

SUSE-SU-2024:2894-1

SUSE-SU-2024:2939-1

SUSE-SU-2024:2947-1

Affected Products

Astra Linux

Linux Kernel

Red Os

Suse

References · 1220

• https://ubuntu.com/security/CVE-2021-47593 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2021-47593 · Vendor Advisory
• http://repo.red-soft.ru/redos/7.3c/x86_64/updates · Vendor Advisory
• https://bdu.fstec.ru/vul/2024-11553 · Security Note
• https://security-tracker.debian.org/tracker/CVE-2021-47593 · Vendor Advisory
• https://osv.dev/vulnerability/UBUNTU-CVE-2021-47593 · Vendor Advisory
• https://git.kernel.org/stable/c/d6692b3b97bdc165d150f4c1505751a323a80717 · Patch
• https://osv.dev/vulnerability/SUSE-SU-2024:2939-1 · Vendor Advisory
• https://osv.dev/vulnerability/SUSE-SU-2024:2947-1 · Vendor Advisory
• https://git.kernel.org/stable/c/c26ac0ea3a91c210cf90452e625dc441adf3e549 · Patch
• https://nvd.nist.gov/vuln/detail/CVE-2021-47593 · Security Note
• https://cve.org/CVERecord?id=CVE-2021-47593 · Security Note
• https://git.kernel.org/stable/c/451f1eded7f56e93aaf52eb547ba97742d9c0e97 · Patch
• https://osv.dev/vulnerability/DEBIAN-CVE-2021-47593 · Vendor Advisory
• https://osv.dev/vulnerability/SUSE-SU-2024:2894-1 · Vendor Advisory