Which versions of Tenda F1202 are affected by EUVD-2026-31634?

Tenda F1202 routers running firmware version 1.2.0.20(408) contain a remotely exploitable memory corruption vulnerability with publicly available exploit code and no vendor-released patch currently…

Is there a public PoC exploit available for EUVD-2026-31634?

Yes, a public proof-of-concept exploit is available for EUVD-2026-31634. Prioritise patching immediately. EPSS: 0.0%.

How to fix or mitigate EUVD-2026-31634?

Within 24 hours: Audit all network infrastructure to identify Tenda F1202 devices and confirm whether they are running firmware version 1.2.0.20(408); document location and network criticality of each affected unit. Within 7 days: Check Tenda's official support website for firmware updates beyond version 1.2.0.20(408); if available, test patched firmware in non-production environment; implement firewall ACLs restricting management interface access to authorized administrator IP ranges only. Within 30 days: Deploy available firmware patches to all vulnerable Tenda F1202 routers, or execute transition plan to migrate to alternative router vendors without this vulnerability.

Tenda F1202 EUVD-2026-31634

Q: What is the CVSS score of EUVD-2026-31634?

EUVD-2026-31634 has a CVSS 4.0 base score of 7.4 (High). CVSS vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. EPSS exploitation probability: 0.0%.

| CVE-2026-9429 HIGH

Stack-based Buffer Overflow (CWE-121)

2026-05-25 VulDB

GHSA-v3rr-p395-8h3q

Tenda Stack Overflow Buffer Overflow F1202

7.4

CVSS 4.0 · Vendor: VulDB

Severity by source

Vendor (VulDB) PRIMARY

7.4 HIGH

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Primary rating from Vendor (VulDB) · only source for this CVE.

CVSS VectorVendor: VulDB

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Lifecycle Timeline

Analysis Generated

Jun 08, 2026 - 09:30 vuln.today

CVSS changed

May 26, 2026 - 20:07 NVD

8.8 (HIGH) 7.4 (HIGH)

DescriptionCVE.org

A vulnerability was found in Tenda F1202 1.2.0.20(408). Affected by this vulnerability is the function formWrlExtraSet of the file /goform/WrlExtraSet. Performing a manipulation of the argument delno results in stack-based buffer overflow. It is possible to initiate the attack remotely. The exploit has been made public and could be used.

AnalysisAI

Stack-based buffer overflow in the Tenda F1202 router (firmware 1.2.0.20(408)) allows remote attackers to corrupt memory by sending a crafted 'delno' parameter to the /goform/WrlExtraSet endpoint handled by the formWrlExtraSet function. Publicly available exploit code exists, though EPSS predicts only a 0.05% exploitation probability (14th percentile), and SSVC classifies the technical impact as total despite the attack not being automatable.

Technical ContextAI

The vulnerability resides in the formWrlExtraSet handler exposed via the /goform/WrlExtraSet web management endpoint on the Tenda F1202 SOHO wireless router. CWE-121 (Stack-based Buffer Overflow) indicates the 'delno' argument is copied into a fixed-size stack buffer without proper length validation, allowing an attacker to overwrite the return address or adjacent stack variables. Tenda /goform/ endpoints are CGI-style handlers implemented in the httpd binary, a recurring source of memory corruption issues in this vendor's MIPS-based embedded firmware. The affected CPE is cpe:2.3:a:tenda:f1202:*:*:*:*:*:*:*:* with the EUVD specifically listing firmware 1.2.0.20(408).

RemediationAI

No vendor-released patch identified at time of analysis - Tenda has not published fixed firmware for the F1202 covering CVE-2026-9429. As compensating controls, restrict access to the router's web management interface (/goform/WrlExtraSet and related endpoints) to trusted LAN management hosts only by disabling Remote/WAN administration, which is the most effective mitigation but removes the ability to manage the device from outside the local network. Enforce strong, unique administrator credentials to raise the PR:L barrier, since exploitation requires authenticated access. Place the device behind a perimeter firewall blocking inbound HTTP/HTTPS to the router's management port from untrusted networks, and monitor https://www.tenda.com.cn/ and https://nvd.nist.gov/vuln/detail/CVE-2026-9429 for firmware updates. If the device is end-of-life or no patch becomes available, plan replacement with a supported model.