CVE-2022-49575 – This CVE describes a race condition vulnerabili... (How to Fix)

Q: What is the severity of CVE-2022-49575?

CVE-2022-49575 has a CVSS score of 4.7 (MEDIUM). This CVE describes a race condition vulnerability in the Linux kernel's TCP implementation where concurrent reading and writing of the sysctl_tcp_thin_linear_timeouts variable could lead to inconsistent behavior. It affects Linux systems with vulnerable kernel versions. The vulnerability could potentially cause unexpected TCP connection behavior or denial of service.

📋 TL;DR

This CVE describes a race condition vulnerability in the Linux kernel's TCP implementation where concurrent reading and writing of the sysctl_tcp_thin_linear_timeouts variable could lead to inconsistent behavior. It affects Linux systems with vulnerable kernel versions. The vulnerability could potentially cause unexpected TCP connection behavior or denial of service.

💻 Affected Systems

Products:

Linux kernel

Versions: Specific vulnerable kernel versions referenced in the git commits

Operating Systems: Linux distributions using affected kernel versions

Default Config Vulnerable: ⚠️ Yes

Notes: Vulnerability exists in the TCP implementation and affects systems where thin linear timeouts are enabled

📦 What is this software?

Linux Kernel by Linux

The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...

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Linux Kernel by Linux

The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...

Learn more about Linux Kernel →

Linux Kernel by Linux

The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...

Learn more about Linux Kernel →

Linux Kernel by Linux

The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...

Learn more about Linux Kernel →

Linux Kernel by Linux

The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...

Learn more about Linux Kernel →

Linux Kernel by Linux

The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...

Learn more about Linux Kernel →

Linux Kernel by Linux

The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...

Learn more about Linux Kernel →

Linux Kernel by Linux

The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...

Learn more about Linux Kernel →

Linux Kernel by Linux

The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...

Learn more about Linux Kernel →

Linux Kernel by Linux

The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...

Learn more about Linux Kernel →

Linux Kernel by Linux

The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...

Learn more about Linux Kernel →

Linux Kernel by Linux

The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...

Learn more about Linux Kernel →

⚠️ Risk & Real-World Impact

🔴

Worst Case

Unstable TCP connections leading to denial of service or unexpected network behavior affecting critical services

🟠

Likely Case

Intermittent TCP connection issues or performance degradation under specific timing conditions

🟢

If Mitigated

Minimal impact with proper kernel patching and system monitoring

🌐 Internet-Facing: LOW - Requires local access or specific timing conditions to exploit

🏢 Internal Only: LOW - Primarily affects local system operations and requires specific conditions

🎯 Exploit Status

Public PoC: ✅ No

Weaponized: NO

Unauthenticated Exploit: ✅ No

Complexity: HIGH - Requires precise timing and local access

Race condition vulnerabilities are difficult to reliably exploit in real-world scenarios

🛠️ Fix & Mitigation

✅ Official Fix

Patch Version: Kernel versions with commits: 404c53ccdebd11f96954f4070cffac8e0b4d5cb6, 492f3713b282c0e67e951cd804edd22eccc25412, 7c6f2a86ca590d5187a073d987e9599985fb1c7c, a0f96c4f179cb3560078cefccef105e8f1701210, cc133e4f4bc225079198192623945bb872c08143

Vendor Advisory: https://git.kernel.org/stable/c/

Restart Required: Yes

Instructions:

1. Update Linux kernel to patched version 2. Reboot system 3. Verify kernel version after reboot

🔧 Temporary Workarounds

Disable thin linear timeouts

linux

Temporarily disable the vulnerable feature by setting sysctl_tcp_thin_linear_timeouts to 0

sysctl -w net.ipv4.tcp_thin_linear_timeouts=0
echo 'net.ipv4.tcp_thin_linear_timeouts = 0' >> /etc/sysctl.conf
sysctl -p

🧯 If You Can't Patch

Implement the sysctl workaround to disable thin linear timeouts
Monitor system logs for TCP connection anomalies and implement network segmentation

🔍 How to Verify

Check if Vulnerable:

Check kernel version against vulnerable versions in git commits

Check Version:

uname -r

Verify Fix Applied:

Verify kernel version matches patched versions and check sysctl_tcp_thin_linear_timeouts value

📡 Detection & Monitoring

Log Indicators:

TCP connection timeouts
Unexpected TCP state changes
Kernel panic or oops messages

Network Indicators:

Unusual TCP retransmission patterns
Connection instability

SIEM Query:

source="kernel" AND ("TCP" OR "timeout") AND severity>=WARNING

📊 Metadata

CVE ID: CVE-2022-49575

CVSS v3 Score: 4.7 (MEDIUM)

CVSS Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H

CWE: CWE-362

EPSS Score: 0.03% exploit probability (7.2th percentile)

Published: February 26, 2025

Last Updated: October 1, 2025

🔗 References

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🔗 Related Vulnerabilities

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