CVE-2026-36779
Description
Tenda O3 Wireless Router v1.0.0.5(4180) has stack overflows in fromVirtualSer, allowing DoS via crafted HTTP requests.
AI Insight
LLM-synthesized narrative grounded in this CVE's description and references.
Tenda O3 Wireless Router v1.0.0.5(4180) has stack overflows in fromVirtualSer, allowing DoS via crafted HTTP requests.
Vulnerability
Multiple stack overflows exist in the fromVirtualSer function of Shenzhen Tenda Technology Co., Ltd Tenda O3 Wireless Router, specifically in version v1.0.0.5(4180) [1]. These vulnerabilities are triggered by user-controlled parameters puVar2, puVar1, __s2, __s1_00, and puVar3 which are retrieved via websGetVar without length validation or sanitization. The sprintf function then performs an unbounded copy, leading to overwrites of adjacent stack memory [1].
Exploitation
An attacker can exploit this vulnerability by sending a crafted HTTP request to the fromVirtualSer CGI endpoint. This request must contain overly long values for any of the parameters puVar2, puVar1, __s2, __s1_00, or puVar3. The vulnerability is reachable if the wans.flag value is set to "1" [1].
Impact
Successful exploitation of these stack overflows can lead to a Denial of Service (DoS) by causing the device to crash or reboot [1]. The references also suggest the potential for arbitrary code execution, although this is not explicitly detailed [1].
Mitigation
Fixed versions and release dates are not yet disclosed in the available references. No workarounds or EOL status are mentioned. The vulnerability has not been listed on the KEV catalog as of the available information [1].
AI Insight generated on Jun 9, 2026. Synthesized from this CVE's description and the cited reference URLs; citations are validated against the source bundle.
Affected products
1- Range: 1.0.0.5(4180)
Patches
0No patches discovered yet.
Vulnerability mechanics
No source-code context for this CVE — mechanics is only generated when we can read the actual fix diff. Without that, the four sections (root cause, attack vector, affected code, fix) would be speculation rather than analysis.
References
1News mentions
0No linked articles in our index yet.