Cyber Posture

CVE-2026-5030

MediumPublic PoC

Published: 29 March 2026

Published
29 March 2026
Modified
30 March 2026
KEV Added
Patch
CVSS Score 6.3 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
EPSS Score 0.0192 83.5th percentile
Risk Priority 14 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-5030 is a medium-severity Injection (CWE-74) vulnerability in Totolink Nr1800X Firmware. Its CVSS base score is 6.3 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 16.5% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified are NIST 800-53 RA-5 (Vulnerability Monitoring and Scanning) and SI-10 (Information Input Validation).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploit Public-Facing Application (T1190) and 1 other technique. What defenders deploy: see the NIST 800-53 controls recommended below.
Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

prevent

Directly prevents command injection by requiring validation of the untrusted host_time input to the NTPSyncWithHost function in cstecgi.cgi.

prevent

Mandates timely remediation of the specific command injection flaw in the Totolink NR1800X firmware to eliminate the vulnerability.

detect

Enables detection of the command injection vulnerability through regular vulnerability scanning of the affected router firmware.

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1059.008 Network Device CLI Execution
Adversaries may abuse scripting or built-in command line interpreters (CLI) on network devices to execute malicious command and payloads.
Why these techniques?

Command injection in router CGI enables exploitation of public-facing application (T1190) and execution of commands via network device CLI (T1059.008).

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

NVD Description

A vulnerability has been found in Totolink NR1800X 9.1.0u.6279_B20210910. This issue affects the function NTPSyncWithHost of the file /cgi-bin/cstecgi.cgi of the component Telnet Service. The manipulation of the argument host_time leads to command injection. The attack can be initiated remotely.…

more

The exploit has been disclosed to the public and may be used.

Deeper analysisAI

CVE-2026-5030 is a command injection vulnerability affecting the Totolink NR1800X router on firmware version 9.1.0u.6279_B20210910. The issue resides in the NTPSyncWithHost function of the /cgi-bin/cstecgi.cgi file within the Telnet Service component, where manipulation of the host_time argument enables command injection. Published on 2026-03-29, it is associated with CWEs-74 and CWE-77 and carries a CVSS v3.1 base score of 6.3 (AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L).

The vulnerability can be exploited remotely by an attacker with low privileges (PR:L), requiring low attack complexity and no user interaction. Successful exploitation allows limited impacts on confidentiality, integrity, and availability through injected commands.

Advisories and additional details, including public exploit disclosure, are available via references such as VulDB entries (vuldb.com/vuln/353952), a proof-of-concept at a Notion site, and the vendor site at www.totolink.net. The exploit has been disclosed to the public and may be used.

Details

CWE(s)

Affected Products

totolink
nr1800x firmware
9.1.0u.6279_b20210910

CVEs Like This One

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CVE-2026-1548Same vendor: Totolink
CVE-2026-5020Same vendor: Totolink
CVE-2026-1150Same vendor: Totolink
CVE-2026-5105Same vendor: Totolink
CVE-2026-5176Same vendor: Totolink

References