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Fencer Intel
critical 9.8

CVE-2026-18686 json

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

published 3mo ago modified 17d 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

Summary

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.

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CISA SSVC

Exploitation
Proof of concept is public
Automatable
yes
Technical impact
total
Assessed
3mo ago

Exploit prediction

4.73% chance of exploitation in the next 30 days, higher than 91% of all scored CVEs (FIRST EPSS, 2026-11-09).

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

Sources

Fencer Intel 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.