CVE-2026-100297 in YSSD-RTMP-H5
Summary
by MITRE • 09/29/2026
In Anjvision YSSD‑RTMP‑H5 firmware version 3.3.2.4, an unauthenticated network check function can be triggered to probe arbitrary hosts from the device’s internal network. This may expose internal information or leak data via DNS queries.
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Analysis
by VulDB Data Team • 09/29/2026
The vulnerability identified in Anjvision YSSD-RTMP-H5 firmware version 3.3.2.4 represents a critical security flaw rooted in improper access control mechanisms within the device's administrative interface. Specifically, an unauthenticated network check function allows any remote actor to interact with internal diagnostic tools without requiring valid credentials or session tokens. This architectural oversight enables attackers to leverage the device as a pivot point for further reconnaissance activities against other systems residing on the same local area network segment. The core technical flaw lies in the failure of the application layer to enforce authentication checks before executing privileged operations, effectively bypassing standard security boundaries that should restrict such functionality to authorized administrators only.
From an operational perspective, this vulnerability facilitates active network scanning and host discovery by external threat actors who can probe arbitrary IP addresses within the internal network topology. The primary mechanism for data exfiltration in this scenario involves Domain Name System queries initiated by the vulnerable function. When a remote attacker specifies target hosts, the device resolves these names via DNS, thereby generating traffic that reveals which internal systems are active and potentially responsive. This process allows attackers to map out the internal network structure, identify live targets, and gather intelligence on the types of services running on those hosts based on their responses or lack thereof. Such information is invaluable for planning subsequent attacks, including targeted exploitation attempts against identified vulnerabilities in other devices.
The implications of this vulnerability extend beyond simple reconnaissance. By exposing internal host availability through DNS leakage, attackers can correlate external-facing assets with internal infrastructure, potentially bridging the gap between perimeter defenses and core network resources. This capability aligns closely with MITRE ATT&CK technique T1046, Network Service Discovery, where adversaries probe networks to identify services for further exploitation. Additionally, it relates to CWE-287, Improper Authentication, as the system fails to verify user identity before allowing sensitive operations. The exposure of internal network dynamics can also lead to secondary issues such as denial-of-service conditions if the probing is conducted at high volumes, or facilitate more sophisticated attacks like man-in-the-middle positioning by identifying specific gateway or server addresses for interception attempts.
Mitigation strategies must focus on immediate remediation and long-term architectural improvements. The most effective solution is to apply the vendor-provided firmware update that patches this unauthenticated access vector if available. In cases where patching is not immediately feasible, network segmentation should be implemented to isolate management interfaces from general user traffic, ensuring that devices with administrative capabilities are only accessible via secure, authenticated channels on restricted VLANs. Furthermore, deploying intrusion detection systems configured to monitor for unusual DNS query patterns originating from IoT or embedded devices can help detect exploitation attempts in real-time. Regular security audits and penetration testing should be conducted to identify similar access control deficiencies across the organization's device inventory, ensuring that diagnostic functions are strictly bound to authenticated administrative contexts only.