CVE-2026-18814 Overview
CVE-2026-18814 is a command injection vulnerability affecting H3C NX15 V100R017 routers. The flaw resides in the reload.reload_config function reachable through the /api/esps endpoint. Attackers can manipulate request parameters to inject operating system commands that execute in the context of the router service. The vendor was contacted before disclosure, and a public exploit is available. The vulnerability is classified under CWE-74: Improper Neutralization of Special Elements in Output Used by a Downstream Component.
Critical Impact
Authenticated attackers can execute arbitrary operating system commands remotely on affected H3C NX15 devices, leading to full compromise of confidentiality, integrity, and availability.
Affected Products
- H3C NX15 running firmware version V100R017
- Router management interface exposing /api/esps
- Deployments using the vulnerable reload.reload_config handler
Discovery Timeline
- 2026-08-04 - CVE-2026-18814 published to the National Vulnerability Database (NVD)
- 2026-08-05 - Last updated in NVD database
- 2026-08-06 - EPSS score recorded at 2.705% (84.516 percentile)
Technical Details for CVE-2026-18814
Vulnerability Analysis
The vulnerability is a remote command injection flaw in the H3C NX15 router firmware. The reload.reload_config function within the /api/esps API endpoint fails to properly neutralize special elements passed through user-controlled input. When an attacker supplies crafted parameter values, the underlying shell interprets injected metacharacters as command separators. The result is arbitrary command execution on the device with the privileges of the web management service, which on embedded network devices typically runs as root.
The attack requires network reachability to the management interface and high privileges according to the CVSS vector. Successful exploitation compromises the confidentiality, integrity, and availability of the affected system. Public proof-of-concept material exists in the GitHub PoC Repository, increasing the likelihood of opportunistic exploitation attempts.
Root Cause
The root cause is improper input neutralization in the reload.reload_config handler. Parameters received by /api/esps are concatenated into a shell command string without sanitization or use of safe execution primitives. Shell metacharacters such as backticks, semicolons, and pipes are passed through to the underlying system shell, allowing attacker-controlled input to alter the intended command.
Attack Vector
The attack is launched remotely over the network against the router management API. An attacker with valid high-privilege credentials sends a crafted request to /api/esps targeting the reload.reload_config function. Injected shell metacharacters cause the router to execute attacker-supplied commands. Additional technical details are available at the VulDB Vulnerability Details page.
No verified exploit code is reproduced here. Refer to the linked PoC repository for technical specifics.
Detection Methods for CVE-2026-18814
Indicators of Compromise
- HTTP requests to the /api/esps endpoint containing shell metacharacters such as ;, |, `, $(, or && in parameter values
- Unexpected outbound connections originating from the router management plane
- New or modified accounts, cron entries, or startup scripts on the device consistent with the service_add_root_rce PoC path
- Web server or management daemon logs referencing reload.reload_config invocations with anomalous arguments
Detection Strategies
- Inspect network traffic to the router management interface for anomalous POST or GET requests targeting /api/esps
- Correlate authentication events with subsequent reload.reload_config calls to identify credential misuse
- Alert on management API requests that include operating system command syntax within parameter values
Monitoring Recommendations
- Centralize router syslog and management API logs for retention and analysis
- Baseline normal administrator activity on /api/esps and alert on deviations in request volume or content
- Monitor for unexpected process execution or configuration changes on affected devices
How to Mitigate CVE-2026-18814
Immediate Actions Required
- Restrict access to the H3C NX15 management interface to trusted administrator networks only
- Rotate all administrative credentials on affected devices to reduce the risk of privileged credential abuse
- Disable remote management from untrusted networks until a vendor patch is applied
- Review device logs for evidence of exploitation targeting /api/esps
Patch Information
No vendor patch reference is listed in the enriched CVE data at time of publication. Consult the VulDB CVE Reference for updates on remediation guidance and contact H3C support for firmware availability for NX15 V100R017.
Workarounds
- Place the router management interface behind a management VLAN or jump host with strict access control lists
- Enforce multi-factor authentication on administrator accounts where supported by the platform
- Deploy network intrusion detection signatures that flag shell metacharacters in requests to /api/esps
- Segment affected devices from user and server networks to limit lateral movement following compromise
# Example ACL restricting management access to a trusted subnet
# Replace 10.0.0.0/24 with your administrator network
acl number 3000
rule 10 permit ip source 10.0.0.0 0.0.0.255
rule 20 deny ip
interface GigabitEthernet0/0
packet-filter 3000 inbound
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
