CVE-2026-86148: Tenda CP3 OS Command Injection Vulnerability

CVE-2026-86148 Overview

CVE-2026-86148 is an operating system command injection vulnerability [CWE-77] in Tenda CP3 firmware version 27.5.57.101. The flaw resides in the SystemAsh function within Apis/system.c of the Kylin component. Attackers can manipulate the AlarmVoiceURL argument to inject arbitrary operating system commands. The vulnerability is exploitable remotely over the network and affects the confidentiality, integrity, and availability of the underlying device.

Critical Impact
Remote attackers with authenticated access can execute arbitrary operating system commands on Tenda CP3 devices, leading to full device compromise.

Affected Products

Tenda CP3 firmware version 27.5.57.101
Kylin component (Apis/system.c)
SystemAsh function processing the AlarmVoiceURL parameter

Discovery Timeline

2026-09-05 - CVE-2026-86148 published to the National Vulnerability Database
2026-09-08 - Last updated in NVD database

Technical Details for CVE-2026-86148

Vulnerability Analysis

The vulnerability exists in the SystemAsh function defined in Apis/system.c, part of the Kylin component in Tenda CP3 27.5.57.101. The function accepts an AlarmVoiceURL parameter from remote clients and passes the value into an operating system command without adequate neutralization of shell metacharacters. An attacker who can reach the management interface can append shell operators to the parameter and execute arbitrary commands in the context of the service process. Successful exploitation compromises the confidentiality, integrity, and availability of the camera and any assets reachable from it.

Root Cause

The root cause is improper neutralization of special elements used in an OS command [CWE-77]. The SystemAsh handler constructs a command string that concatenates the attacker-controlled AlarmVoiceURL value directly into a shell invocation. No allowlist validation, escaping, or safe API is applied before execution, allowing arbitrary command chaining via characters such as ;, |, &, or backticks.

Attack Vector

Exploitation occurs remotely over the network by issuing a crafted request to the vulnerable Kylin endpoint that processes AlarmVoiceURL. The attacker embeds shell metacharacters and additional commands within the parameter value. When the device parses the request, the injected commands execute with the privileges of the handling process. According to available metrics, the current EPSS probability of exploitation is 2.465% at the 83.531 percentile.

Refer to the VulDB CVE Entry and VulDB Vulnerability Record for further technical detail.

Detection Methods for CVE-2026-86148

Indicators of Compromise

Inbound HTTP or API requests to Kylin endpoints containing shell metacharacters such as ;, |, &, $(), or backticks inside the AlarmVoiceURL parameter.
Unexpected child processes spawned by the Tenda CP3 web service, particularly sh, wget, curl, nc, or busybox invocations.
Outbound connections from the camera to unfamiliar IP addresses or download of secondary payloads.

Detection Strategies

Deploy network intrusion detection signatures that inspect HTTP request bodies and query strings for command injection patterns targeting AlarmVoiceURL.
Baseline the expected process tree of the Tenda CP3 firmware and alert when the web handler process spawns shell interpreters or network utilities.
Correlate device syslog entries with firewall telemetry to identify anomalous outbound traffic from IoT segments.

Monitoring Recommendations

Forward device and network logs to a centralized analytics platform for retention and correlation across the IoT fleet.
Monitor management interfaces for authentication anomalies and repeated requests to camera configuration endpoints.
Alert on DNS lookups from camera subnets to non-approved destinations, which may indicate staged payload retrieval.

How to Mitigate CVE-2026-86148

Immediate Actions Required

Restrict network access to Tenda CP3 management interfaces to trusted administrative networks only, using firewall or VLAN segmentation.
Rotate administrative credentials on all Tenda CP3 devices and enforce strong, unique passwords.
Inventory affected devices running firmware version 27.5.57.101 and prioritize them for isolation or replacement.

Patch Information

At the time of publication, no vendor advisory or patch has been referenced for CVE-2026-86148. Monitor the Tenda Official Website for firmware updates addressing this vulnerability. Review the VulDB CTI Analysis for updates on remediation status.

Workarounds

Block external access to the camera's HTTP management interface at the perimeter firewall and permit only jump-host access.
Place affected cameras on an isolated VLAN with egress filtering to prevent outbound connections initiated by compromised devices.
Disable remote administration features on the device where operationally acceptable until a vendor patch is available.

bash

# Example: restrict access to Tenda CP3 management interface
iptables -A INPUT -p tcp --dport 80 -s 10.0.0.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A FORWARD -s 192.168.50.0/24 -d 0.0.0.0/0 -j DROP