CyberSecBulletin
CVE-2022-36558NVD status: Modified

Skybridge Mb-a100 Firmware: Use of Hard-coded Credentials

CVE-2022-36558 is a critical-severity use of hard-coded credentials vulnerability in Skybridge Mb-a100 Firmware from Seiko-sol, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected Skybridge Mb-a100 Firmware versions: 4.2.0 and earlier. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.81% chance of exploitation within 30 days, higher than 57% of scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Check which version of Skybridge Mb-a100 Firmware you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on seiko-sol.co.jp for workarounds and exact fixed builds.
  3. 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
Seiko-solSkybridge Mb-a100 Firmware4.2.0 and earlierNot stated
Seiko-solSkybridge Mb-a110 Firmware4.2.0 and earlierNot 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
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
HighThe component can be taken down completely.

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

Official description

Seiko SkyBridge MB-A100/A110 v4.2.0 and below implements a hard-coded passcode for the root account. Attackers are able to access the passcord via the file /etc/ciel.cfg.

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

The underlying weakness: Use of Hard-coded Credentials

The product contains hard-coded credentials, such as a password or cryptographic key.

How developers prevent this class of flaw

  • For outbound authentication: store passwords, keys, and other credentials outside of the code in a strongly-protected, encrypted configuration file or database that is protected from access by all outsiders, including other local users on the same system. Properly protect the key (CWE-320). If you cannot use encryption to protect the file, then make sure that the permissions are as restrictive as possible. In Windows environments, the Encrypted File System (EFS) may provide some protection.
  • For inbound authentication: Rather than hard-code a default username and password, key, or other authentication credentials for first time logins, utilize a first login mode that requires the user to enter a unique strong password or key.
  • If the product must contain hard-coded credentials or they cannot be removed, perform access control checks and limit which entities can access the feature that requires the hard-coded credentials. For example, a feature might only be enabled through the system console instead of through a network connection.

More Use of Hard-coded Credentials vulnerabilities (CWE-798)

Timeline

  1. CVE record published.
  2. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Skybridge Mb-a100 Firmware

All Skybridge Mb-a100 Firmware vulnerabilities

Recent Use of Hard-coded Credentials vulnerabilities

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