Description
A vulnerability, which was classified as critical, has been found in TOTOLINK EX1200T 4.1.2cu.5232_B20210713. This issue affects the function setLanguageCfg of the file /cgi-bin/cstecgi.cgi. The manipulation of the argument LangType leads to stack-based buffer overflow. The attack may be initiated remotely. The exploit has been disclosed to the public and may be used.
EPSS Score:
0%
Comprehensive Technical Analysis of EUVD-2025-16902
1. Vulnerability Assessment and Severity Evaluation
The vulnerability EUVD-2025-16902, also known as CVE-2025-5600, is classified as critical. It involves a stack-based buffer overflow in the setLanguageCfg function of the /cgi-bin/cstecgi.cgi file in TOTOLINK EX1200T firmware version 4.1.2cu.5232_B20210713. The manipulation of the LangType argument can lead to this overflow, which can be exploited remotely.
Severity Evaluation:
- CVSS Base Score: 9.3
- CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
The high base score indicates a severe vulnerability due to the following factors:
- Attack Vector (AV:N): Network, meaning the vulnerability can be exploited remotely.
- Attack Complexity (AC:L): Low, indicating that the attack is relatively straightforward to execute.
- Privileges Required (PR:N): None, meaning no special privileges are needed to exploit the vulnerability.
- User Interaction (UI:N): None, meaning no user interaction is required for the attack to succeed.
- Confidentiality (VC:H), Integrity (VI:H), and Availability (VA:H): All high, indicating significant impact on all three aspects of the CIA triad.
2. Potential Attack Vectors and Exploitation Methods
Attack Vectors:
- Remote Exploitation: An attacker can send specially crafted requests to the vulnerable
setLanguageCfgfunction over the network. - Manipulation of
LangTypeArgument: By manipulating theLangTypeargument, an attacker can cause a stack-based buffer overflow, leading to arbitrary code execution.
Exploitation Methods:
- Buffer Overflow: The attacker can send a payload that exceeds the buffer size allocated for the
LangTypeargument, causing the stack to overflow. - Code Execution: Once the buffer overflow occurs, the attacker can inject malicious code to gain control over the device.
3. Affected Systems and Software Versions
Affected Systems:
- TOTOLINK EX1200T devices running firmware version 4.1.2cu.5232_B20210713.
Software Versions:
- Firmware version 4.1.2cu.5232_B20210713.
4. Recommended Mitigation Strategies
Immediate Mitigation:
- Network Segmentation: Isolate affected devices from critical networks to limit potential damage.
- Firewall Rules: Implement strict firewall rules to block unauthorized access to the vulnerable CGI script.
- Monitoring: Increase monitoring of network traffic to detect and respond to suspicious activities.
Long-Term Mitigation:
- Firmware Update: Apply the latest firmware updates from TOTOLINK as soon as they are available.
- Patch Management: Implement a robust patch management process to ensure timely updates.
- Security Audits: Conduct regular security audits and vulnerability assessments to identify and mitigate similar issues.
5. Impact on European Cybersecurity Landscape
The vulnerability poses a significant risk to the European cybersecurity landscape, particularly for organizations and individuals using TOTOLINK EX1200T devices. The potential for remote exploitation and the high impact on confidentiality, integrity, and availability make it a critical concern. Organizations must prioritize patching and implementing robust security measures to mitigate the risk.
6. Technical Details for Security Professionals
Vulnerability Details:
- Function:
setLanguageCfg - File:
/cgi-bin/cstecgi.cgi - Argument:
LangType - Issue: Stack-based buffer overflow
Exploitation Steps:
- Identify Target: Locate TOTOLINK EX1200T devices running the vulnerable firmware version.
- Craft Payload: Create a payload that exceeds the buffer size for the
LangTypeargument. - Send Request: Send the crafted request to the vulnerable CGI script.
- Execute Code: Inject and execute malicious code to gain control over the device.
Detection and Response:
- Intrusion Detection Systems (IDS): Deploy IDS to detect unusual network traffic patterns indicative of exploitation attempts.
- Log Analysis: Regularly analyze logs for signs of unauthorized access or unusual activity.
- Incident Response: Have an incident response plan in place to quickly address and mitigate any successful exploitation.
References:
By addressing this vulnerability promptly and effectively, organizations can significantly reduce the risk of exploitation and ensure the security of their networks and devices.