CyberSecBulletin
CVE-2023-50922NVD status: Modified

Gl-mt1300 Firmware: Unrestricted Upload of File with Dangerous Type

CVE-2023-50922 is a high-severity unrestricted upload of file with dangerous type vulnerability in Gl-mt1300 Firmware from GL.iNet, with a CVSS 3.1 base score of 7.2 out of 10. It can be exploited remotely over the network by an attacker with administrator privileges, without any action from a user. Affected Gl-mt1300 Firmware versions: 4.3.7. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.86% chance of exploitation within 30 days, higher than 59% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of Gl-mt1300 Firmware you run against the affected versions below, and install the vendor's latest release.

Affected products and versions

VendorProductAffected versionsFixed in
Gl-inetGl-mt1300 Firmware4.3.7Not stated
Gl-inetGl-mt300n-v2 Firmware4.3.7Not stated
Gl-inetGl-ar750s Firmware4.3.7Not stated
Gl-inetGl-ar750 Firmware4.3.7Not stated
Gl-inetGl-ar300m Firmware4.3.7Not stated
Gl-inetGl-b1300 Firmware4.3.7Not stated
Gl-inetGl-mt6000 Firmware4.5.0Not stated
Gl-inetGl-a1300 Firmware4.4.6Not stated
Gl-inetGl-ax1800 Firmware4.4.6Not stated
Gl-inetGl-axt1800 Firmware4.4.6Not stated
Gl-inetGl-mt3000 Firmware4.4.6Not stated
Gl-inetGl-mt2500 Firmware4.4.6Not stated

Version data comes from NVD's product matching. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
HighAdministrator-level access is required first.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.2HighNVD
CVSS 3.17.2HighCISA (ADP)

Official description

An issue was discovered on GL.iNet devices through 4.5.0. Attackers who are able to steal the AdminToken cookie can execute arbitrary code by uploading a crontab-formatted file to a specific directory and waiting for its execution. This affects A1300 4.4.6, AX1800 4.4.6, AXT1800 4.4.6, MT3000 4.4.6, MT2500 4.4.6, MT6000 4.5.0, MT1300 4.3.7, MT300N-V2 4.3.7, AR750S 4.3.7, AR750 4.3.7, AR300M 4.3.7, and B1300 4.3.7.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Unrestricted Upload of File with Dangerous Type

The product allows the upload or transfer of dangerous file types that are automatically processed within its environment.

How developers prevent this class of flaw

  • Generate a new, unique filename for an uploaded file instead of using the user-supplied filename, so that no external input is used at all.
  • When the set of acceptable objects, such as filenames or URLs, is limited or known, create a mapping from a set of fixed input values (such as numeric IDs) to the actual filenames or URLs, and reject all other inputs.
  • Consider storing the uploaded files outside of the web document root entirely. Then, use other mechanisms to deliver the files dynamically.

More Unrestricted Upload of File with Dangerous Type vulnerabilities (CWE-434)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Technical write-ups (may include proof of concept)

Other vulnerabilities in Gl-mt1300 Firmware

All Gl-mt1300 Firmware vulnerabilities

Recent Unrestricted Upload of File with Dangerous Type vulnerabilities

Spotted an error? Tell us.