CVE-2026-19983
CVE-2026-19983 — GL.iNet XE3000 NAS Command Service gl_nas_sys os command injection
A vulnerability was detected in GL.iNet A1300, AX1800, AXT1800, MT2500, MT3000, MT6000, X3000 and XE3000 4.8.x. This issue affects some unknown processing of the file /usr/bin/gl_nas_sys of the component NAS Command Service. The manipulation results in os command injection. The attack may be launched remotely. Upgrading to version 4.9.0 is capable of addressing this issue. It is suggested to upgrade the affected component. The vendor explains: "After our investigation, we have confirmed that the vulnerability described (...) does indeed exist."
Published Updated Sources: NVD, GL.iNet (CNA), GitHub, SOCRadar CTI
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.
Exploitation
Exploit code
public exploit, none observed
EPSS
0%
ahead of 0% of scored CVEs
CVSS base
8.3
high · 6 sources
Remediation
The vendor's own words where we have them.
Upgrade A1300 to a fixed release (4.9.0). Apply vendor patches per advisory and restrict external exposure of the affected component until patched.
First 24 hours
Ordered from the record's own fields — exposure first, because you cannot patch what you have not found.
- Identify exposed assets running affected vendor/product/version combinations.
- Prioritize based on EPSS, PoC availability, and external exposure.
- Search available logs for exploit probes, errors, authentication anomalies, or suspicious child processes matching the vulnerability class.
Affected scope
Vendor, product and version as the advisories word them.
| Vendor | Product | Versions | Status |
|---|---|---|---|
| GL.iNet | A1300 | 4.8.* | Vulnerable |
| GL.iNet | A1300 | 4.9.0 | Patched |
| GL.iNet | AX1800 | 4.8.* | Vulnerable |
| GL.iNet | AX1800 | 4.9.0 | Patched |
| GL.iNet | AXT1800 | 4.8.* | Vulnerable |
| GL.iNet | AXT1800 | 4.9.0 | Patched |
| GL.iNet | MT2500 | 4.8.* | Vulnerable |
| GL.iNet | MT2500 | 4.9.0 | Patched |
| GL.iNet | MT3000 | 4.8.* | Vulnerable |
| GL.iNet | MT3000 | 4.9.0 | Patched |
| GL.iNet | MT6000 | 4.8.* | Vulnerable |
| GL.iNet | MT6000 | 4.9.0 | Patched |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Availability
Low
Confidentiality
Low
Integrity
Low
Scope
Changed
Attack Complexity
Low
Attack Vector
Network
Privileges Req
None
User Interaction
None
Every base score collected
Sources score independently and disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Source |
|---|---|---|---|---|---|
| 8.3 | CVSS 3.1 | high | 3.9 | 3.7 | NVD |
| 7.5 | CVSS 2.0 | high | 10 | 6.4 | vuldb.com (CNA) |
| 6.9 | CVSS 4.0 | medium | — | — | GL.iNet (CNA) |
| 8.3 | CVSS 3.1 | high | — | — | GL.iNet (CNA) |
| 8.3 | CVSS 3.0 | high | — | — | GL.iNet (CNA) |
| 7.5 | CVSS 2.0 | high | — | — | GL.iNet (CNA) |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L
What this weakness leads to
MITRE's own consequences and mitigations for the weakness class — the authority's wording, not guidance derived from the CVSS vector.
CWE-78 · Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
- Execute Unauthorized Code or Commands
- DoS: Crash, Exit, or Restart
- Read Files or Directories
- Modify Files or Directories
Mitigation: If at all possible, use library calls rather than external processes to recreate the desired functionality.
CWE-77 · Improper Neutralization of Special Elements used in a Command ('Command Injection')
- Execute Unauthorized Code or Commands
Mitigation: If at all possible, use library calls rather than external processes to recreate the desired functionality.
Weakness & attack patterns
- CWE-78OS Command Injection
- CWE-77Command Injection
Attack patterns reported against this CVE. The ATT&CK techniques below are inferred from its weakness class.
Public exploit
Capability, not use: code existing is a different claim from anyone running it.
Repositories
1
Detection
Read off the CVSS vector and the weakness class. Starting points, not rules we have tested.
- Search application, proxy, and WAF logs for requests touching /usr/bin/gl_nas_sys.
- Prioritize edge telemetry for network-reachable A1300, AX1800, AXT1800, MT2500, MT3000, MT6000, X3000, XE3000.
- Monitor for scanner or exploit-pattern traffic after 1 public PoC repositories were reported.
Timeline
What happened to this CVE, newest first — with the readings a source repeats on a schedule counted underneath rather than listed.
- 2026
Added · CVSS 3.1 8.3 (AV:N)
Aug 17, 2026 · NVD
Initial · CVE published
Aug 17, 2026 · NVD
CVE published by mitre
Aug 17, 2026 · SOCRadar CTI
Reported · Advisory disclosed
Aug 16, 2026 · GL.iNet
Reported · VulDB entry created
Aug 16, 2026 · GL.iNet
Reported · VulDB entry last update
Aug 16, 2026 · GL.iNet
Source activity
Readings a source repeats on a schedule, counted rather than listed.
- 1×CVE modified by NIST, Cweid, Modified, LinkAug 17, 2026 · SOCRadar CTI
References
5 on the record
- github.com/gl-inet/CVE-issues/blob/main/4.0.0/NAS%20Host-header%20bypass%20to%20unauthenticated%20root%20RCE.md
Exploit, Third Party Advisory, NIST
- vuldb.com/cve/CVE-2026-19983
Vendor Advisory
- vuldb.com/submit/873919
Vendor Advisory
- vuldb.com/vuln/391165
Vendor Advisory
- vuldb.com/vuln/391165/cti
Vendor Advisory
Coverage
1 story from the feeds we poll
Elsewhere on this site
- GL.iNetevery CVE for this vendor
- Remote Code Execsame class
- CWE-78other pages naming this weakness
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record1
What should defenders know first?
CVE-2026-19983 is GL.iNet XE3000 NAS Command Service gl_nas_sys os command injection, a high vulnerability affecting A1300, AX1800, AXT1800, MT2500, MT3000, MT6000, X3000, XE3000 from GL.iNet. The current evidence does not list it in CISA KEV, and the exploit status is: Active exploitation is not confirmed from current sources for CVE-2026-19983. Public exploit evidence is: 1 public PoC repositories reported; 0 marked weaponized in current dataset. The affected-version evidence is listed in the key facts and affected products tables. Defenders should first verify whether exposed or business-critical assets run those versions, then apply vendor patches or mitigations, restrict reachable attack surface, and preserve logs for detection review. CVSS 8.3 describes technical severity, while EPSS 0% helps estimate near-term exploit likelihood; neither replaces asset context. Unknown fields should remain explicit in tickets, and threat actor, IOC, victimology, or payload claims should not be added unless a cited source supports them. Monitor CISA KEV, vendor advisories, NVD changes, public PoC repositories, and internal telemetry for update triggers.