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CVE-2023-24544NVD status: Modified

BS-GSL and BS-GS series: Improper Access Control

CVE-2023-24544 is a high-severity improper access control vulnerability in BS-GSL and BS-GS series from Buffalo, with a CVSS 3.1 base score of 8.1 out of 10. It can be exploited from the same local network by an unauthenticated attacker, without any action from a user. There is no confirmed exploitation so far. EPSS estimates a 0.29% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Bs-gs2016p Firmware to 1.1.7.01 or a later version.
  2. Update Bs-gs2024p Firmware to 1.1.7.01 or a later version.
  3. Update Bs-gs2016hp Firmware to 1.1.7.01 or a later version.
  4. Read the advisory on buffalo.jp for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
BUFFALOBS-GSL and BS-GS seriesNot specified in the recordNot stated
BuffaloBs-gsl2024 Firmware1.10-0.03 and earlierNot stated
BuffaloBs-gsl2016p Firmware1.10-0.03 and earlierNot stated
BuffaloBs-gsl2016 Firmware1.10-0.03 and earlierNot stated
BuffaloBs-gs2008 Firmware1.0.10.01 and earlierNot stated
BuffaloBs-gs2016 Firmware1.0.10.01 and earlierNot stated
BuffaloBs-gs2024 Firmware1.0.10.01 and earlierNot stated
BuffaloBs-gs2048 Firmware1.0.10.01 and earlierNot stated
BuffaloBs-gs2008p Firmware1.0.10.01 and earlierNot stated
BuffaloBs-gs2016p Firmware1.0.10.01 and earlier; before 1.1.7.011.1.7.01
BuffaloBs-gs2024p Firmware1.0.10.01 and earlier; before 1.1.7.011.1.7.01
BuffaloBs-gs2016hp Firmwarebefore 1.1.7.011.1.7.01
BuffaloBs-gs2024hp Firmwarebefore 1.1.7.011.1.7.01

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
AdjacentThe attacker must be on the same local network segment.
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
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
NoneAvailability is not affected.

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

Scoring systemScoreSeverityScored by
CVSS 3.18.1HighNVD
CVSS 3.18.1HighCISA (ADP)

Official description

Improper access control vulnerability in Buffalo network devices allows a network-adjacent attacker to obtain specific files of the product. As a result, the product settings may be altered. The affected products and versions are as follows: BS-GSL2024 firmware Ver. 1.10-0.03 and earlier, BS-GSL2016P firmware Ver. 1.10-0.03 and earlier, BS-GSL2016 firmware Ver. 1.10-0.03 and earlier, BS-GS2008 firmware Ver. 1.0.10.01 and earlier, BS-GS2016 firmware Ver. 1.0.10.01 and earlier, BS-GS2024 firmware Ver. 1.0.10.01 and earlier, BS-GS2048 firmware Ver. 1.0.10.01 and earlier, BS-GS2008P firmware Ver. 1.0.10.01 and earlier, BS-GS2016P firmware Ver. 1.0.10.01 and earlier, and BS-GS2024P firmware Ver. 1.0.10.01 and earlier

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

The underlying weakness: Improper Access Control

The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor.

How developers prevent this class of flaw

  • Very carefully manage the setting, management, and handling of privileges. Explicitly manage trust zones in the software.
  • Compartmentalize the system to have safe areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area. Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.

More Improper Access Control vulnerabilities (CWE-284)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Other vulnerabilities in BS-GSL and BS-GS series

All BS-GSL and BS-GS series vulnerabilities

Recent Improper Access Control vulnerabilities

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