GL.iNet GL-MT3000 nas-web RPC Wrapper glc nas-web.add_user command injection

published 2026-08-04 3 mo ago modified 2026-10-23 16 d ago also EUVD-2026-52547

cvss: 9.8; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 4.7%; EPSS 4.7% chance of exploitation in 30 days, percentile 91%
public exploits: 0; none known

A vulnerability was detected in GL.iNet GL-MT3000 up to 4.4.5. The affected element is the function nas-web.add_user of the file /cgi-bin/glc of the component nas-web RPC Wrapper. Performing a manipulation results in command injection. The attack can be initiated remotely. The exploit is now public and may be used. The vendor was contacted early about this disclosure and confirmed the existence of the vulnerability.

CISA SSVC

Exploitation: Proof of concept is public
Automatable: yes
Technical impact: total
Assessed: 3 mo ago (2026-08-04)

Exploit prediction

4.73% chance of exploitation in the next 30 days, higher than 91% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/coconut652-7/IOT_Vul_Public/tree/main/Glinet/MT3000/nas-web/ADD_USER_ADD_SHARE referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	4.0	9.3	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P
CNA	3.1	9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:P/RL:X/RC:R
CNA	3.0	9.8	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:P/RL:X/RC:R
CNA	2.0	10.0	AV:N/AC:L/Au:N/C:C/I:C/A:C/E:POC/RL:ND/RC:C
CNA	4.0	8.9	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CNA	3.1	9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA	2.0	10.0	AV:N/AC:L/Au:N/C:C/I:C/A:C

Affected products

GL.iNet GL-MT3000

Classification

Weakness

CWE-77 Improper Neutralization of Special Elements used in a Command
CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component

References

github.com /coconut652-7/IOT_Vul_Public/tree/main/Glinet/MT3000/nas-web/ADD_USER_ADD_SHARE
exploit
vuldb.com /vuln/385612
vdb-entry, technical-description
vuldb.com /vuln/385612/cti
signature, permissions-required
vuldb.com /cve/CVE-2026-18686
third-party-advisory
vuldb.com /submit/856139
third-party-advisory

Sources

CVE List CVE-2026-18686
NVD CVE-2026-18686

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary