CVE-2024-3721
Published: April 11, 2026
Official Description
A vulnerability was found in TBK DVR-4104 and DVR-4216 up to 20240412 and classified as critical. This issue affects some unknown processing of the file /device.rsp?opt=sys&cmd=___S_O_S_T_R_E_A_MAX___. The manipulation of the argument mdb/mdc leads to os command injection. The attack may be initiated remotely.
Technical Analysis
CVE-2024-3721 requires local access, meaning attackers must already have a foothold on the target system.
Exploitation requires some privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
CISA has added CVE-2024-3721 to the Known Exploited Vulnerabilities (KEV) catalog, confirming active exploitation in the wild. U.S. federal agencies are required to patch this within the mandated timeframe, and all organizations should treat remediation as urgent.
Exploit & PoC Resources
News & Research Mentioning CVE-2024-3721
FortiGuard Labs has identified a Mirai-based Nexcorium campaign actively exploiting CVE-2024-3721 in TBK DVR devices
Threat actors are exploiting security flaws in TBK DVR and end‑of‑life (EoL) TP-Link Wi-Fi routers to deploy Mirai-botnet variants on compromised devices, according to findings from Fortinet FortiGuard Labs and Palo Alto Networks Unit 42. The attack targeting TBK DVR devices has been found to exploit CVE-2024-3721 (CVSS score: 6.3), a medium-severity command injection vulnerability affecting [xlite_meta score:59 src:The Hacker News xlite_fp:2b7fc50a1e11235ef54ed2f91b06b1d06d2390e15173b0d2787cf83d33104dbf]
Quick Facts
Known Threat Actors
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2024-3721 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
- !CISA KEV: Federal agencies must patch per BOD 22-01 timeline
- !Active exploitation confirmed — treat as P1