CVE-2024-7172 in A3600R
Summary
by MITRE • 07/29/2024
A vulnerability classified as critical was found in TOTOLINK A3600R 4.1.2cu.5182_B20201102. Affected by this vulnerability is the function getSaveConfig of the file /cgi-bin/cstecgi.cgi?action=save&setting. The manipulation of the argument http_host leads to buffer overflow. The attack can be launched remotely. The exploit has been disclosed to the public and may be used. The identifier VDB-272593 was assigned to this vulnerability. NOTE: The vendor was contacted early about this disclosure but did not respond in any way.
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Analysis
by VulDB Data Team • 08/06/2024
The vulnerability identified as CVE-2024-7172 represents a critical buffer overflow flaw within the TOTOLINK A3600R router firmware version 4.1.2cu.5182_B20201102. This issue specifically affects the getSaveConfig function in the /cgi-bin/cstecgi.cgi script, which handles configuration saving operations through the action=save&setting parameters. The vulnerability arises from improper input validation when processing the http_host argument, creating an exploitable condition that allows attackers to manipulate memory boundaries through crafted input sequences. The affected router model represents a common consumer-grade device that typically serves as a central networking hub in residential and small office environments, making it a potentially attractive target for widespread exploitation.
The technical implementation of this buffer overflow vulnerability stems from insufficient bounds checking in the processing of the http_host parameter within the cgi-bin interface. When an attacker submits a malformed http_host value containing excessive data, the application fails to properly validate the input length before copying it into a fixed-size buffer, resulting in memory corruption that can overwrite adjacent memory segments. This type of vulnerability aligns with CWE-121, which describes stack-based buffer overflow conditions where insufficient bounds checking allows attackers to write beyond allocated buffer boundaries. The remote exploitation capability means that an attacker does not require physical access to the device, as the vulnerability can be triggered through network-based attacks targeting the web management interface.
The operational impact of this vulnerability extends beyond simple denial of service or data corruption, as it creates potential for complete system compromise and persistent access to affected networks. Attackers who successfully exploit this vulnerability could gain unauthorized administrative access to the router configuration, potentially enabling them to modify network settings, redirect traffic, install malicious firmware, or establish persistent backdoors. The disclosure of an exploit for this vulnerability increases the risk of widespread exploitation, particularly given that many users may not update their router firmware regularly. This scenario aligns with ATT&CK technique T1059.007, which covers command and scripting interpreter usage, as attackers could leverage compromised routers to execute malicious commands within target networks.
Mitigation strategies for CVE-2024-7172 should prioritize immediate firmware updates from TOTOLINK, although the vendor's lack of response to early disclosure raises concerns about the availability of patched versions. Network administrators should implement additional security controls including firewall rules that restrict access to the router's web management interface, particularly when the device is exposed to untrusted networks. The use of network segmentation and monitoring can help detect anomalous traffic patterns that might indicate exploitation attempts. Security professionals should also consider disabling unnecessary services and ports, implementing strong authentication mechanisms, and regularly auditing router configurations to identify any unauthorized changes that might indicate successful exploitation. Organizations should maintain awareness of the vulnerability through security advisories and consider alternative network security measures such as intrusion detection systems that can identify patterns consistent with buffer overflow exploitation attempts.