CVE-2023-51971: Critical Stack Overflow in Tenda AX1803 Router

CVE-2023-51971 is a critical stack buffer overflow in the getIptvInfo function of Tenda AX1803 firmware 1.0.0.1, reached through the adv.iptv.stbpvid parameter. NVD scores it 9.8. No fixed firmware is confirmed in the record, so check Tenda's support site and keep the router's admin interface off the internet.

What's affected

CVE-2023-51971 affects Tenda AX1803 firmware version 1.0.0.1. NVD published it on 2024-01-10 with a score of 9.8 (critical) and the vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H: reachable over the network, low complexity, no privileges and no user interaction.

The record says the getIptvInfo function contains a stack overflow through the adv.iptv.stbpvid parameter. The record names only firmware 1.0.0.1, and I found no vendor advisory or fixed version, so check Tenda's support site.

This is one of a set of near identical findings. The same function family, getIptvInfo, has the sibling CVEs CVE-2023-51967, CVE-2023-51968, CVE-2023-51969, and the other IPTV related functions have more. Each is its own CVE for a different parameter, so a router that is vulnerable to one is very likely to be vulnerable to the rest.

Weakness class: CWE-787.

How to check if you're exposed

Find your Tenda AX1803 units and read the firmware version in the router's admin interface, or on the product label for the hardware revision. Menu names vary by firmware. The record names version 1.0.0.1, so a unit reporting that version is in scope.

Then check how the admin interface is reachable. If remote management is enabled on the WAN side, or the router sits in a DMZ, the web service answers to the internet. From a machine outside your network, test whether the router's web port responds. If your ISP supplied the device, ask the ISP who manages its firmware.

Safeguard's free in-browser dependency scan at gold.safeguard.sh/scan checks the open source packages you ship. It does not inspect appliance firmware or a vendor's closed product, so for this CVE the useful work is asset inventory and vendor follow-up.

What to do now

1. Inventory every Tenda AX1803 and note the firmware version. Pay attention to routers at remote sites and homes of staff who work remotely.
2. Check Tenda's support site for firmware newer than 1.0.0.1 and read its release notes. I could not confirm a fixed version from the sources available, so verify it yourself before you rely on an update.
3. Turn off remote web management and make sure the admin interface listens only on the LAN side.
4. Use a strong, unique administrator password, and keep untrusted devices off the network segment that can reach the router's admin page.
5. If no fixed firmware exists and the device protects something important, plan to replace it with a model that receives security updates.

Why it matters

CWE-787 covers writes past the end of a buffer. Here the buffer is on the stack, so an oversized value for adv.iptv.stbpvid can overwrite neighbouring data, including the saved return address of the function. That is the classic route from a long string to control of a program.

It is notable how many entries share one pattern. The IPTV settings handlers read many parameters into fixed size buffers, and each unchecked copy became a separate CVE. A fix for one parameter that leaves the others open will leave the device vulnerable, so ask Tenda that the whole family be corrected. The record's KEV flag is false and I found no advisory that reports exploitation. Embedded devices often have limited memory protections, which is why overflows on them tend to be taken seriously.

Quick check

Sources

Reporter write-up on Notion (listed in the record; the page did not return readable content when I fetched it)

NVD record for CVE-2023-51971 (the record this guide is built from)

Last reviewed: 19 October 2026.