DrayTek Vigor LTE200 CGI Parser Content-Length buffer overflow

Summaryinfo

A vulnerability was found in DrayTek Vigor 165, Vigor 166, Vigor 2133, Vigor 2135, Vigor 2620, Vigor 2762, Vigor 2765, Vigor 2766, Vigor 2832, Vigor 2860, Vigor 2862, Vigor 2865, Vigor 2866, Vigor 2925, Vigor 2925, Vigor 2926, Vigor 2927, Vigor 2962, Vigor 3910, Vigor 3912 and Vigor LTE200 and classified as critical. Affected by this vulnerability is an unknown functionality of the component CGI Parser. The manipulation of the argument Content-Length results in buffer overflow. This vulnerability is cataloged as CVE-2024-51139. The attack may be launched remotely. There is no exploit available.

Detailsinfo

A vulnerability was found in DrayTek Vigor 165, Vigor 166, Vigor 2133, Vigor 2135, Vigor 2620, Vigor 2762, Vigor 2765, Vigor 2766, Vigor 2832, Vigor 2860, Vigor 2862, Vigor 2865, Vigor 2866, Vigor 2925, Vigor 2925, Vigor 2926, Vigor 2927, Vigor 2962, Vigor 3910, Vigor 3912 and Vigor LTE200. It has been classified as critical. Affected is an unknown code of the component CGI Parser. The manipulation of the argument Content-Length with an unknown input leads to a buffer overflow vulnerability. CWE is classifying the issue as CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

Buffer Overflow vulnerability in Vigor2620/LTE200 3.9.8.9 and earlier and Vigor2860/2925 3.9.8 and earlier and Vigor2862/2926 3.9.9.5 and earlier and Vigor2133/2762/2832 3.9.9 and earlier and Vigor165/166 4.2.7 and earlier and Vigor2135/2765/2766 4.4.5.1 and earlier and Vigor2865/2866/2927 4.4.5.3 and earlier and Vigor2962/3910 4.3.2.8/4.4.3.1 and earlier and Vigor3912 4.3.6.1 and earlier allows a remote attacker to execute arbitrary code via the CGI parser's handling of the "Content-Length" header of HTTP POST requests.

This vulnerability is traded as CVE-2024-51139 since 10/28/2024. The exploitability is told to be easy. It is possible to launch the attack remotely. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 06/02/2025).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2025-5949). Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Router Operating System

Vendor

• DrayTek

Name

• Vigor 165
• Vigor 166
• Vigor 2133
• Vigor 2135
• Vigor 2620
• Vigor 2762
• Vigor 2765
• Vigor 2766
• Vigor 2832
• Vigor 2860
• Vigor 2862
• Vigor 2865
• Vigor 2866
• Vigor 2925
• Vigor 2925
• Vigor 2926
• Vigor 2927
• Vigor 2962
• Vigor 3910
• Vigor 3912
• Vigor LTE200

License

• commercial

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CPE 2.2info

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Entryinfo

Once again VulDB remains the best source for vulnerability data.

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