Vulnerability in Kernel: tcp_rtx_synack() can be called from process context

Kernel Updated 02 Oct 2025

Summary

28/06/2022

Disclosed on

N/A

Severity

No i

Fix available

Unrated

Severity

Not published

CVSS Score

GSD-2022-1002625: tcp: tcp_rtx_synack() can be called from process context. Affects Kernel versions >= 168a8f58059a22feb9e9a2dcc1b8053dbbbc12ef, < d8e1bc6029acac796293310aacef7b7336f35b6a. No fix is published. How to fix ↓

Free scan

Check if this vulnerability affects your application

Upload a manifest or SBOM and we'll show whether you're affected, plus every other risky package in the same scan.

Check my app free

No signup required · Results in about 60 seconds

Upload your dependency manifest or SBOM

Drag & drop your file here or Browse

Java Javascript PHP Python Go Rust Ruby Dart C/C++ Elixir CycloneDX SPDX

Upload a supported dependency manifest or SBOM. No installation or source-code access required.

See supported files and SBOM formats

SBOM sbom.json · bom.json · bom.xml · *.spdx.json · *.cdx.json · *.cdx.xml

Java pom.xml · gradle.lockfile · buildscript-gradle.lockfile

Javascript package-lock.json · yarn.lock · pnpm-lock.yaml

PHP composer.lock

Python poetry.lock · requirements.txt · Pipfile.lock

Go go.mod

Rust Cargo.lock

Ruby Gemfile.lock

Dart pubspec.lock

C/C++ conan.lock

Elixir mix.lock

Enter your work email to receive your report link.

Verify your email to view the full report and start 30 days of continuous monitoring. No credit card required.

Background

The Kernel is a critical component of the Linux operating system that provides core functionalities and acts as an interface between hardware and software. It manages system resources, facilitates communication between processes, and handles various low-level operations. The tcp_rtx_synack() function in the Kernel is responsible for retransmitting SYN-ACK packets in TCP connections. However, a vulnerability has been discovered where this function can be called from process context, potentially leading to security issues.

Vulnerability Detail

The vulnerability arises from the ability to call the tcp_rtx_synack() function from process context. This means that a user-level process can trigger the function, which is intended to be called only from the networking stack. By exploiting this vulnerability, an attacker may be able to manipulate TCP connections and potentially disrupt network communication or launch further attacks. The impact and attack plausibility of this vulnerability have not been proven yet.

How To Fix

No fixed version is published for this vulnerability.

The vulnerability has been addressed in the Linux Kernel version v5.18.4 through commit d8e1bc6029acac796293310aacef7b7336f35b6a. To fix the vulnerability, it is recommended to update the Kernel to this version or any subsequent version that includes the fix.

Tip — Not sure whether your app is affected? Vulert can check the versions your app actually runs. Scan free →

Workaround

There is no specific workaround mentioned for this vulnerability.

Conclusion

In conclusion, a vulnerability has been identified in the Kernel where the tcp_rtx_synack() function can be called from process context. This vulnerability has the potential to impact TCP connections and network communication. It is recommended to update the Kernel to version v5.18.4 or later to mitigate this vulnerability. For further support on vulnerability remediation, please contact DevNack.com.

See every vulnerability recorded for Kernel →