CyberSecBulletin
CVE-2023-31472NVD status: Modified

Gl-s20 Firmware: Allocation of Resources Without Limits or Throttling

CVE-2023-31472 is a high-severity allocation of resources without limits or throttling vulnerability in Gl-s20 Firmware from GL.iNet, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 3.216 as the first without the flaw, so updating Gl-s20 Firmware to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 19.9% chance of exploitation within 30 days, which is in the top 2.53% of all scored CVEs.

Patch this week

EPSS places it among the vulnerabilities most likely to be exploited soon.

What to do

  1. Update Gl-s20 Firmware to 3.216 or a later version.
  2. Update Gl-x3000 Firmware to 3.216 or a later version.
  3. Update Gl-mt3000 Firmware to 3.216 or a later version.
  4. Read the advisory on github.com for workarounds and exact fixed builds.
  5. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Gl-inetGl-s20 Firmwarebefore 3.2163.216
Gl-inetGl-x3000 Firmwarebefore 3.2163.216
Gl-inetGl-mt3000 Firmwarebefore 3.2163.216
Gl-inetGl-mt2500 Firmwarebefore 3.2163.216
Gl-inetGl-mt2500a Firmwarebefore 3.2163.216
Gl-inetGl-axt1800 Firmwarebefore 3.2163.216
Gl-inetGl-a1300 Firmwarebefore 3.2163.216
Gl-inetGl-ax1800 Firmwarebefore 3.2163.216
Gl-inetGl-sft1200 Firmwarebefore 3.2163.216
Gl-inetGl-mt1300 Firmwarebefore 3.2163.216
Gl-inetGl-e750 Firmwarebefore 3.2163.216
Gl-inetGl-mv1000 Firmwarebefore 3.2163.216
Gl-inetGl-mv1000w Firmwarebefore 3.2163.216
Gl-inetGl-s10 Firmwarebefore 3.2163.216
Gl-inetGl-s200 Firmwarebefore 3.2163.216
Gl-inetGl-s1300 Firmwarebefore 3.2163.216
Gl-inetGl-sf1200 Firmwarebefore 3.2163.216
Gl-inetGl-b1300 Firmwarebefore 3.2163.216
Gl-inetGl-b2200 Firmwarebefore 3.2163.216
Gl-inetGl-ap1300 Firmwarebefore 3.2163.216
Gl-inetGl-ap1300lte Firmwarebefore 3.2163.216
Gl-inetGl-x1200 Firmwarebefore 3.2163.216
Gl-inetGl-x750 Firmwarebefore 3.2163.216
Gl-inetGl-x300b Firmwarebefore 3.2163.216
Gl-inetGl-xe300 Firmwarebefore 3.2163.216

Version data comes from NVD's product matching; 7 further products are omitted here. 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
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
NoneNo data is disclosed.
Integrity
HighData or code can be modified at will.
Availability
NoneAvailability is not affected.

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

Scoring systemScoreSeverityScored by
CVSS 3.17.5HighNVD
CVSS 3.17.5HighCISA (ADP)

Official description

An issue was discovered on GL.iNet devices before 3.216. There is an arbitrary file write in which an empty file can be created anywhere on the filesystem. This is caused by a command injection vulnerability with a filter applied.

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

The underlying weakness: Allocation of Resources Without Limits or Throttling

The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.

How developers prevent this class of flaw

  • Clearly specify the minimum and maximum expectations for capabilities, and dictate which behaviors are acceptable when resource allocation reaches limits.
  • Limit the amount of resources that are accessible to unprivileged users. Set per-user limits for resources. Allow the system administrator to define these limits. Be careful to avoid CWE-410.
  • For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.

More Allocation of Resources Without Limits or Throttling vulnerabilities (CWE-770)

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

Other vulnerabilities in Gl-s20 Firmware

All Gl-s20 Firmware vulnerabilities

Recent Allocation of Resources Without Limits or Throttling vulnerabilities

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