Tenda O3 1.0.0.5(4180) HTTP fromVirtualSer puVar3 stack-based overflow

Summaryinfo

A vulnerability has been found in Tenda O3 1.0.0.5(4180) and classified as critical. The impacted element is the function fromVirtualSer of the component HTTP Handler. The manipulation of the argument puVar3 leads to stack-based overflow. This vulnerability is uniquely identified as CVE-2026-36779. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability was found in Tenda O3 1.0.0.5(4180). It has been rated as critical. This issue affects the function fromVirtualSer of the component HTTP Handler. The manipulation of the argument puVar3 with an unknown input leads to a stack-based overflow vulnerability. Using CWE to declare the problem leads to CWE-121. A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function). Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Shenzhen Tenda Technology Co., Ltd Tenda O3 Wireless Router v1.0.0.5(4180) was discovered to contain multiple stack overflows in the fromVirtualSer function via the puVar2, puVar1, __s2, __s1_00, and puVar3 parameters. These vulnerabilities allow attackers to cause a Denial of Service (DoS) via a crafted HTTP request.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-36779 since 04/06/2026. The exploitation is known to be easy. The attack may be initiated remotely. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 06/09/2026).

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

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• Router Operating System

Vendor

• Tenda

Name

• O3

Version

• 1.0.0.5(4180)

License

• commercial

Website

• Vendor: https://www.tenda.com.cn/

CPE 2.3info

• 🔒

CPE 2.2info

• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Discussion