CVE-2026-51380 Tenda CVE debrief

Who should care

Security teams and administrators responsible for Tenda AC10 v3 devices, especially those using firmware V03.03.16.09, should be aware of this vulnerability and take immediate action to mitigate the risk. Additionally, network administrators, IT teams, and cybersecurity professionals should review the affected systems and networks to assess the potential impact and implement necessary controls to prevent exploitation.

Technical summary

The CVE-2026-51380 vulnerability is a Buffer Overflow issue in the /cgi-bin/UploadCfg endpoint of Tenda AC10 v3 (firmware V03.03.16.09). This vulnerability has a CVSS score of 9.8 and is classified as Critical. The vulnerability could allow attackers to cause a permanent Denial of Service (DoS) or potentially execute remote code. The buffer overflow occurs when the endpoint receives a specially crafted request that exceeds the buffer size, allowing an attacker to inject malicious code. This could lead to a complete compromise of the affected system.

Defensive priority

High

Recommended defensive actions

• Apply the vendor's official patch or update to a version that addresses this vulnerability.
• Implement network segmentation to limit the attack surface.
• Monitor network traffic for suspicious activity related to the /cgi-bin/UploadCfg endpoint.
• Consider using a Web Application Firewall (WAF) to detect and prevent buffer overflow attacks.
• Review compensating controls for exposed systems while remediation is scheduled and verified.
• Track exceptions, retest remediated assets, and close the item only after evidence is documented.
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.

Evidence notes

The CVE record was published on 2026-07-15T21:16:54.437Z and was last modified on 2026-07-16T16:19:12.127Z. The NVD entry is currently Deferred. The vulnerability details are based on the information provided in the CVE record and the NVD database. The evidence for this vulnerability is limited to the information provided by the CVE and NVD sources. Further verification and review of the affected systems and networks are necessary to confirm the existence and impact of this vulnerability.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.