CyberSecBulletin
CVE-2023-38555NVD status: Modified

Si-R 30B: Improper Authentication

Published Updated By the CyberSecBulletin desk

CVE-2023-38555 is a high-severity improper authentication vulnerability in Si-R 30B from Fujitsu, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited from the same local network by an unauthenticated attacker, without any action from a user. Affected Si-R 30B versions: All versions. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.37% 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. Check which version of Si-R 30B you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on fujitsu.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
FujitsuSi-R 30BAll versionsNot stated
FujitsuSi-R 130BAll versionsNot stated
FujitsuSi-R 90brinAll versionsNot stated
FujitsuSi-R570BAll versionsNot stated
FujitsuSi-R370BAll versionsNot stated
FujitsuSi-R220DAll versionsNot stated
FujitsuSi-R G100V02.54 and earlierNot stated
FujitsuSi-R G200V02.54 and earlierNot stated
FujitsuSi-R G100BV04.12 and earlierNot stated
FujitsuSi-R G110BV04.12 and earlierNot stated
FujitsuSi-R G200BV04.12 and earlierNot stated
FujitsuSi-R G210V20.52 and earlierNot stated
FujitsuSi-R G211V20.52 and earlierNot stated
FujitsuSi-R G120V20.52 and earlierNot stated
FujitsuSi-R G121V20.52 and earlierNot stated
FujitsuSR-M 50AP1All versionsNot stated
FujitsuSi-r 30b FirmwareNot specified in the recordNot stated
FujitsuSi-r 130b FirmwareNot specified in the recordNot stated
FujitsuSi-r 90brin FirmwareNot specified in the recordNot stated
FujitsuSi-r570b FirmwareNot specified in the recordNot stated
FujitsuSi-r370b FirmwareNot specified in the recordNot stated
FujitsuSi-r220d FirmwareNot specified in the recordNot stated
FujitsuSi-r G100 Firmware02.54 and earlierNot stated
FujitsuSi-r G200 Firmware02.54 and earlierNot stated
FujitsuSi-r G100b Firmware04.12 and earlierNot stated

Version data comes from the organisation that assigned the CVE; 7 further products are omitted here. 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
HighThe component can be taken down completely.

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

Official description

Authentication bypass vulnerability in Fujitsu network devices Si-R series and SR-M series allows a network-adjacent unauthenticated attacker to obtain, change, and/or reset configuration settings of the affected products. Affected products and versions are as follows: Si-R 30B all versions, Si-R 130B all versions, Si-R 90brin all versions, Si-R570B all versions, Si-R370B all versions, Si-R220D all versions, Si-R G100 V02.54 and earlier, Si-R G200 V02.54 and earlier, Si-R G100B V04.12 and earlier, Si-R G110B V04.12 and earlier, Si-R G200B V04.12 and earlier, Si-R G210 V20.52 and earlier, Si-R G211 V20.52 and earlier, Si-R G120 V20.52 and earlier, Si-R G121 V20.52 and earlier, and SR-M 50AP1 all versions.

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

The underlying weakness: Improper Authentication

When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.

How developers prevent this class of flaw

  • Use an authentication framework or library such as the OWASP ESAPI Authentication feature.

More Improper Authentication vulnerabilities (CWE-287)

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

Recent Improper Authentication vulnerabilities

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