CVE-2022-3635 in Linux
Summary
by MITRE • 10/21/2022
A vulnerability, which was classified as critical, has been found in Linux Kernel. Affected by this issue is the function tst_timer of the file drivers/atm/idt77252.c of the component IPsec. The manipulation leads to use after free. It is recommended to apply a patch to fix this issue. VDB-211934 is the identifier assigned to this vulnerability.
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Analysis
by VulDB Data Team • 05/18/2025
The vulnerability identified as CVE-2022-3635 represents a critical use-after-free flaw within the Linux kernel's ATM (Asynchronous Transfer Mode) subsystem, specifically affecting the IDT77252 driver implementation. This vulnerability resides in the tst_timer function located within drivers/atm/idt77252.c, which is part of the IPsec component architecture. The flaw manifests when the kernel processes certain ATM network operations, creating conditions where memory that has been freed is subsequently accessed, leading to potential system instability or exploitation by malicious actors. The vulnerability's classification as critical indicates the severe impact this flaw can have on system security and stability.
The technical implementation of this use-after-free vulnerability occurs through improper memory management within the IPsec processing pipeline of the ATM driver. When the tst_timer function executes, it handles timer events associated with ATM network connections, particularly those involving IPsec encryption and decryption operations. The flaw arises from the driver's failure to properly validate memory references after certain operations have freed allocated resources, creating a scenario where subsequent code execution attempts to access memory that has already been deallocated. This memory corruption can result in arbitrary code execution, privilege escalation, or system crashes that compromise the integrity of the kernel space operations.
The operational impact of CVE-2022-3635 extends beyond simple system instability to encompass potential full system compromise and data breach scenarios. Systems running affected Linux kernel versions that utilize ATM networking with IPsec functionality are particularly vulnerable, as the flaw can be exploited through network-based attacks that trigger the problematic code path. The vulnerability affects systems that implement ATM networking stacks, including those used in telecommunications infrastructure, enterprise networking equipment, and specialized industrial control systems. The use-after-free condition creates opportunities for attackers to execute malicious code with kernel-level privileges, potentially leading to complete system takeover and persistent backdoor establishment.
Mitigation strategies for CVE-2022-3635 require immediate patch application from Linux kernel maintainers, as the vulnerability cannot be effectively addressed through configuration changes or workarounds. Organizations should prioritize updating their kernel versions to include the official patches released by the Linux kernel security team, which address the memory management issues within the IDT77252 driver. System administrators should also implement network segmentation and monitoring to detect potential exploitation attempts, particularly focusing on unusual ATM traffic patterns or IPsec connection anomalies. Additionally, the vulnerability aligns with CWE-416, which specifically addresses use-after-free conditions, and may be categorized under ATT&CK technique T1059 for command and scripting interpreter usage, as exploitation could involve executing malicious code through compromised kernel processes.
The broader implications of this vulnerability highlight the critical importance of kernel security auditing and memory safety validation in network subsystem implementations. The flaw demonstrates how complex networking protocols within kernel space can introduce subtle but severe security issues that may remain undetected for extended periods. Organizations utilizing Linux-based systems with ATM networking capabilities should conduct comprehensive security assessments to identify potential exploitation vectors and implement robust monitoring solutions to detect anomalous behavior that might indicate successful exploitation attempts. The vulnerability serves as a reminder of the need for continuous security validation and the importance of maintaining up-to-date kernel implementations to protect against known and emerging threats in the cybersecurity landscape.