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CVE-2024-3721 is a remote OS command injection vulnerability affecting TBK DVR-4104 and DVR-4216 digital video recorder devices. The flaw is exposed through the HTTP endpoint /device.rsp with the query string opt=sys&cmd=S_O_S_T_R_E_A_MAX, where improper handling of the mdb and mdc parameters allows attacker-controlled input to be interpreted as operating system commands. The vulnerable processing occurs without authentication, enabling a remote attacker to send a crafted HTTP request and execute arbitrary commands on the device. Public exploit code has been disclosed, and the vulnerability has been observed in active exploitation campaigns delivering Mirai-family botnet malware such as Nexcorium, Broadside, ShadowV2, and RondoDox.
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1 valid exploit after Mallory filtered fakes, detection scripts, and README-only repos (1 hidden).
This repository contains a single C source file ('tbk.c') implementing a network-based exploit targeting embedded devices (likely TBK DVRs or similar IoT devices) with an HTTP service exposing a '/device.rsp' endpoint. The exploit operates as a scanner, establishing up to 256 concurrent TCP connections to random IP addresses (with some filtering to avoid reserved/private ranges) on port 80. For each connection, it attempts to send a crafted HTTP POST request to the '/device.rsp' endpoint, injecting a shell command that downloads and executes a binary ('arm7') from a remote server (92.246.90.22). The exploit is operational, as it automates both the scanning and exploitation process, and the payload provides remote code execution on the target. The code is self-contained but references some external headers (not included), likely for utility and randomization functions. The main attack vector is network-based, and the exploit is designed for mass exploitation of vulnerable IoT devices.
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103 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
A vulnerability in TBK digital video recorders exploited by the Nexus Team campaign to deploy the Nexcorium botnet malware.
An unauthenticated remote code execution vulnerability in TBK digital video recorders that is being exploited to deploy the Mirai-based Nexcorium botnet malware.
A vulnerability in TBK DVR devices that was abused in a recent campaign to gain access and deliver the Nexcorium Mirai variant, contributing to a vulnerability-driven IoT botnet campaign.
A command injection vulnerability in TBK DVR devices that is being exploited to deploy the Nexcorium Mirai variant and conscript devices into a DDoS botnet.
Query your assets running an affected version, and investigate the blast radius.
Every observed campaign linking this CVE to a named adversary.
Malware families riding this exploit, with evidence and IOCs.
YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.
Cross-references every affected SKU, including bundled OEM variants.
Community discussion across Reddit, Mastodon, and other social sources.