PT-2024-11038 · Linux+4 · Linux Kernel+4

Qingyu Li · Published 2021-03-01 · Updated 2024-10-09 · CVE-2021-4442

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 A vulnerability has been resolved in the Linux kernel related to the TCP QUEUE SEQ option. The issue was reported by Qingyu Li, who found a syzkaller bug that changes the RCV SEQ after restoring data in the receive queue. This should not be allowed, as TCP QUEUE SEQ should only be used when queues are empty. The patch fixes this case and the tx path as well. The vulnerability can be exploited locally, allowing an attacker to gain elevated privileges.

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

Exploit

RCE

Weakness Enumeration

CWE-20

Related Identifiers

BDU:2025-02863

CESA-2021_4356

CVE-2021-4442

RHSA-2021:4356

RHSA-2021_4356

SUSE-SU-2024:3566-1

SUSE-SU-2024_3566-1

Affected Products

Astra Linux

Centos

Linux Kernel

Red Hat

Suse

References · 216

• 🔥 https://git.kernel.org/stable/c/319f460237fc2965a80aa9a055044e1da7b3692a · Exploit
• 🔥 https://git.kernel.org/stable/c/8811f4a9836e31c14ecdf79d9f3cb7c5d463265d · Exploit
• 🔥 https://git.kernel.org/stable/c/3bf899438c123c444f6b644a57784dfbb6b15ad6 · Exploit
• 🔥 https://git.kernel.org/stable/c/3b72d5a703842f582502d97906f17d6ee122dac2 · Exploit
• 🔥 https://git.kernel.org/stable/c/046f3c1c2ff450fb7ae53650e9a95e0074a61f3e · Exploit
• https://cve.org/CVERecord?id=CVE-2021-4442 · Security Note
• https://osv.dev/vulnerability/UBUNTU-CVE-2021-4442 · Vendor Advisory
• https://security-tracker.debian.org/tracker/CVE-2021-4442 · Vendor Advisory
• https://bdu.fstec.ru/vul/2025-02863 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2021-4442 · Security Note
• https://ubuntu.com/security/CVE-2021-4442 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2021-4442 · Vendor Advisory
• https://osv.dev/vulnerability/DEBIAN-CVE-2021-4442 · Vendor Advisory
• https://osv.dev/vulnerability/SUSE-SU-2024:3566-1 · Vendor Advisory
• https://suse.com/security/cve/CVE-2024-44999 · Note