CVE-2025-9828 Overview
CVE-2025-9828 affects the Tenda CP6 IP camera running firmware version 11.10.00.243. The vulnerability resides in the sub_2B7D04 function within the uhttp component. Manipulation of this function results in the use of a risky cryptographic algorithm [CWE-310]. The flaw is remotely reachable over the network without authentication, though exploitation carries high complexity. Public disclosure of the exploit technique has occurred, raising the risk that attackers may adopt it against exposed devices.
Critical Impact
Remote unauthenticated attackers can potentially compromise the confidentiality of data protected by the weak cryptographic algorithm implemented in the uhttp service.
Affected Products
- Tenda CP6 IP camera hardware
- Tenda CP6 firmware 11.10.00.243
- Deployments exposing the uhttp web interface to untrusted networks
Discovery Timeline
- 2025-09-02 - CVE-2025-9828 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-9828
Vulnerability Analysis
The vulnerability exists in the sub_2B7D04 function within the uhttp component of the Tenda CP6 firmware. This function implements or invokes a cryptographic routine that relies on a weak or outdated algorithm, classified under [CWE-310] Cryptographic Issues. Because uhttp handles HTTP-based communication with the camera, the weak cryptography likely protects data in transit, session material, or authentication artifacts.
An attacker positioned on the network can attempt to break the cryptographic protection through brute force, known cryptanalytic techniques, or observation of predictable output. The attack complexity is rated high, indicating that exploitation requires specialized knowledge or specific preconditions. Public disclosure of the exploit means detailed information is available to threat actors monitoring vulnerability feeds.
Root Cause
The root cause is the selection and implementation of a cryptographic algorithm that no longer meets modern security standards. Common examples include short key lengths, deprecated ciphers such as DES or RC4, weak hashing like MD5 or SHA-1, or insecure modes of operation. The sub_2B7D04 function performs cryptographic operations without leveraging contemporary primitives resistant to known attacks.
Attack Vector
Exploitation requires network access to the Tenda CP6 device, typically to the HTTP interface exposed by the uhttp daemon. An attacker captures traffic or interacts with cryptographic endpoints handled by sub_2B7D04. The attacker then applies cryptanalysis to recover plaintext, keys, or authentication tokens. Because the attack is described as difficult, meaningful exploitation may depend on capturing sufficient ciphertext or executing precise timing observations.
See the GitHub Firmware Update Guide and VulDB #322175 for additional technical context.
Detection Methods for CVE-2025-9828
Indicators of Compromise
- Unexpected HTTP requests targeting the uhttp service on the Tenda CP6 device
- Anomalous session or authentication activity originating from devices communicating with the camera
- Presence of firmware version 11.10.00.243 on internet-exposed CP6 hardware
Detection Strategies
- Inventory network devices to identify Tenda CP6 cameras running the affected firmware
- Inspect TLS or cryptographic handshakes performed by the camera for deprecated cipher suites or short key lengths
- Monitor for prolonged packet capture activity targeting the camera's HTTP endpoints, which may indicate offline cryptanalysis preparation
Monitoring Recommendations
- Log and alert on inbound connections to the CP6 management interface from unexpected source addresses
- Use network traffic analysis to flag use of weak cipher suites negotiated by the uhttp service
- Correlate camera authentication events with subsequent access to protected video streams for signs of credential compromise
How to Mitigate CVE-2025-9828
Immediate Actions Required
- Restrict network access to the Tenda CP6 camera by isolating it on a management VLAN or behind a firewall
- Block internet exposure of the uhttp service and any HTTP-based administrative interface
- Rotate any credentials or shared secrets stored on or transmitted by affected cameras
Patch Information
No vendor patch is referenced in the enriched CVE data at the time of publication. Operators should monitor the Tenda Official Website for firmware updates addressing the weak cryptography in sub_2B7D04. Until a fix is available, compensating controls at the network layer are required.
Workarounds
- Place the CP6 camera behind a reverse proxy or VPN that terminates TLS using modern cipher suites before traffic reaches the device
- Disable remote management features and limit administrative access to trusted internal hosts only
- Segment IoT devices from production networks to contain the impact of a cryptographic compromise
- Replace the affected hardware if the vendor does not release a firmware update addressing [CWE-310]
# Example firewall rule to restrict access to the CP6 management interface
iptables -A INPUT -p tcp --dport 80 -s 192.0.2.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -d <camera_ip> -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
