Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A06:2021 - Vulnerable and Outdated Components
ASVS 5.0
V15 - Secure Coding and Architecture Bounds checking, buffer size validation
MITRE ATT&CK
2 techniques across 2 tactics: Execution, Privilege Escalation The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | This vulnerability presents CRITICAL real-world risk despite requiring authentication (PR:L). Attack Vector Network (AV:N) and Low Complexity (AC:L) indicate no special conditions needed to trigger exploitation. The CVSS 3.1 score of 8.8 appropriately reflects high severity. The public POC disclosure significantly elevates real-world risk—defenders cannot rely on obscurity. While the PR:L requirement (authenticated attacker) is a mitigating factor, Tenda routers are frequently deployed with default credentials or weak authentication, reducing practical barrier to entry. EPSS score (if available) would likely indicate high exploitation probability given public POC and network-accessible target. This is NOT a theoretical high-CVSS-low-risk issue; rather, it represents an active threat to deployed Tenda FH1203 devices. Organizations should prioritize patching based on exposure to these routers in their infrastructure. |
| Exploit ScenarioDerived | An attacker with valid credentials (obtained through default credentials, credential reuse, or phishing) accesses the Tenda FH1203 web interface remotely via HTTP/HTTPS on port 80/443. The attacker crafts a POST request to /goform/AdvSetLanip with an oversized lanMask parameter containing a buffer overflow payload (shellcode or ROP chain). The vulnerable fromadvsetlanip function copies this input without bounds checking into a stack buffer, corrupting the return address. Upon function return, execution jumps to attacker-controlled code, granting arbitrary command execution with root privileges on the router. The attacker can then pivot to compromise internal networks, establish persistence, exfiltrate traffic, or use the router as a botnet node. The public POC eliminates need for custom exploit development, making this accessible to low-skilled attackers. |
Get an e-mail when this CVE is exploited, patched or re-scored. Free account.
Alert meAnalysisAIv1 – Mar 14, 2026
Critical remote buffer overflow vulnerability in Tenda FH1203 firmware version 2.0.1.6 affecting the /goform/AdvSetLanip endpoint. An authenticated attacker can exploit improper input validation of the lanMask parameter to achieve remote code execution with full system compromise (confidentiality, integrity, and availability). A public proof-of-concept exploit exists, indicating active disclosure and potential real-world exploitation risk.
RemediationAI
Immediate actions: (1) Check for available firmware updates from Tenda's official support website or admin interface (Settings > System Tools > Firmware Upgrade). (2) If patched firmware is available for FH1203, upgrade immediately. (3) Temporary workarounds while awaiting patch: disable remote management access, restrict web interface access to trusted networks only via firewall rules, change default credentials to strong unique passwords, monitor router logs for suspicious /goform/AdvSetLanip requests. (4) Consider network segmentation to isolate router management traffic. (5) Monitor Tenda's security advisories at tenda.com.cn or regional support sites for patch availability. Without access to specific vendor advisory links in provided references, recommend checking Tenda support directly and security databases (NVD, Exploit-DB) for patch version information once released.
Affected VersionsENISA
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 1 package in euvd
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
The vulnerability exists in the fromadvsetlanip function within the Tenda FH1203 router's web administration interface. Tenda FH1203 is a residential WLAN router running proprietary firmware. The vulnerability is classified as CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer), a classic stack-based buffer overflow caused by insufficient bounds checking on the lanMask parameter. The affected endpoint /goform/AdvSetLanip handles LAN IP configuration requests and fails to validate the length of user-supplied input before copying it into a fixed-size buffer. This allows an authenticated attacker to overwrite adjacent stack memory, potentially hijacking control flow to execute arbitrary code with router privileges. CPE identifier: cpe:2.3:o:tenda:fh1203_firmware:2.0.1.6:*:*:*:*:*:*:*
Know when Fh1203 Firmware gets its next vulnerability
- Watch products and get an email when something new is published
- Check this CVE against your own stack and servers
- Exploit and PoC references, threat intelligence from 22 sources
No credit card · 7-day full trial
Severity by source
AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
Lifecycle Timeline
2DescriptionCVE.org
A vulnerability, which was classified as critical, was found in Tenda FH1203 2.0.1.6. Affected is the function fromadvsetlanip of the file /goform/AdvSetLanip. The manipulation of the argument lanMask leads to buffer overflow. It is possible to launch the attack remotely. The exploit has been disclosed to the public and may be used.
Executive ViewAI
A critical remote code execution vulnerability exists in Tenda FH1203 wireless routers (version 2.0.1.6) affecting the LAN configuration function. Organizations using this equipment face immediate risk of unauthorized network access and potential lateral movement into internal systems, with active exploits already public and weaponized.
Restrict network access to router administration interfaces (block external WAN access to /goform/AdvSetLanip endpoint); implement Web Application Firewall (WAF) rules to filter malicious lanMask parameter values; apply strict input validation at network boundary; segment router management traffic onto isolated administrative VLAN; disable remote management features if not required; monitor for exploitation attempts; consider hardware replacement pending firmware availability from vendor.
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
A buffer overflow occurs when a program writes more data to a memory buffer than it was allocated to hold, causing the excess data to spill into adjacent memory regions.
More in Fh1203 Firmware
View allTenda FH1203 v2.0.1.6 has a stack overflow vulnerability in the schedStartTime parameter of the setSchedWifi function. R
Tenda F1203 V2.0.1.6, FH1203 V2.0.1.6 and FH1205 V2.0.0.7(775) were discovered to contain a stack overflow via the ssid
Tenda AC10 V1.0 V15.03.06.23, AC1206 V15.03.06.23, AC6 V2.0 V15.03.06.23, AC7 V1.0 V15.03.06.44, AC5 V1.0 V15.03.06.28,
Tenda F1203 V2.0.1.6, FH1203 V2.0.1.6 and FH1205 V2.0.0.7(775) was discovered to contain a stack overflow via the device
Tenda AC6 V2.0 V15.03.06.23, AC7 V1.0 V15.03.06.44, F1203 V2.0.1.6, AC5 V1.0 V15.03.06.28, FH1203 V2.0.1.6 and AC9 V3.0
Tenda AC10 V1.0 V15.03.06.23, AC1206 V15.03.06.23, AC8 v4 V16.03.34.06, AC6 V2.0 V15.03.06.23, AC7 V1.0 V15.03.06.44, F1
Tenda FH1203 V2.0.1.6 was discovered to contain a stack overflow via the page parameter in the fromVirtualSer function.
Tenda FH1203 V2.0.1.6 was discovered to contain a stack overflow via the entrys parameter in the fromAddressNat function
Tenda FH1203 V2.0.1.6 was discovered to contain a stack overflow via the page parameter in the fromAddressNat function.
Tenda FH1203 V2.0.1.6 was discovered to contain a stack overflow via the deviceId parameter in the formSetClientState fu
Tenda FH1203 V2.0.1.6 was discovered to contain a stack overflow via the speed_dir parameter in the formSetSpeedWan func
Tenda FH1203 V2.0.1.6 was discovered to contain a stack overflow via the deviceId parameter in the formSetDeviceName fun
EUVD-2025-18378
NVD
CVE.org
EPSS
VulDB
GitHub PoC
Exploit-DB