Evidence used
- No CISA KEV confirmation is currently recorded.
- EPSS is 0.37% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2023
CVE-2023-38555High confidence
Fujitsu Limited Si-R 30B — Improper Authentication
Fujitsu Limited · Si-R 30B
8.8HighCVSS 3.1
Within 7 days
Fix not verifiedHigh technical severity; prioritise exposed affected systems while verifying vendor guidance.
R
Open reassessment dashboard →Operational reassessment
Published severity in operational context
Published severityHigh→Operational priority:High, unchanged from published severity.unchanged
Compensating controls
- Restrict local access and enforce least privilege on affected hosts.
- Monitor vendor guidance and exploitation sources for a material change.
Verification
- Confirm that the asset runs Fujitsu Limited Si-R 30B and falls inside the recorded affected range.
- Recheck the vendor advisory before scheduling a change because no verified fixed version is currently retained.
- Validate exposure, authentication requirements and compensating controls in the actual environment.
- Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
High technical severity; prioritise exposed affected systems while verifying vendor guidance.
Fix not verified01
What, why and how
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.
What
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.
Why
The affected component does not establish the requesting party's identity reliably before granting access.
How
An attacker operating through the affected interface may attempt exploitation without authentication or user interaction. If successful, the issue may bypass an access boundary or take over an account.
What
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.
Why
The affected component does not establish the requesting party's identity reliably before granting access.
How
An attacker operating through the affected interface may attempt exploitation without authentication or user interaction. If successful, the issue may bypass an access boundary or take over an account.
02
Exploit reality and attack path
CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.
Observed exploitation No confirmed evidence
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.
Public PoC / exploit material None recorded
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.
- Likely attack path
- the affected interface → Improper Authentication → bypass an access boundary or take over an account
- Attack surface
- Unspecified
- Privileges required
- None: unauthenticated exploitation is possible
- User interaction
- None
- Attack complexity
- Low: no specialised conditions are recorded
- Security boundary
- Unchanged: impact remains within the vulnerable component's security authority
- Weakness
?
CWE means Common Weakness Enumeration: a standard category for the underlying weakness. - CWE-287 ↗
CWE-287: Improper Authentication. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.
- CVSS vector
?
CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity. CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HCommon Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.
AVAdjacentAttack vector: The attacker must be on an adjacent or logically close network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CHighConfidentiality impact: A successful attack can cause a major loss.IHighIntegrity impact: A successful attack can cause a major loss.AHighAvailability impact: A successful attack can cause a major loss.- Post-exploitation / living off the land
- Stolen credentials, tokens and legitimate administration functions may provide continued access without deploying a large custom toolset.
03
Patch and workaround
Operational remediation based on structured source evidence.
- Status
?
Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change. - Fix not verified
- Affected
- 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
- SR-M 50AP1: All versions
- Fixed
- No fixed version is explicitly recorded in the structured CVE data.
- Action
- No verified patch reference is present in the current structured sources. Check the vendor advisory before making a change.
- Workaround
- No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04
Evidence and provenance
Published 26 Jul 2023 · Last source change 14 Nov 2024, 15:00 UTC · CWE-287 · Improper Authentication
CVE recordCVE.org · 5.1
CVSS sourceNIST NVD
EPSS source FIRST · tracked since 2026-08-14
?
The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.European sourceENISA EUVD · EUVD-2023-42354
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceNIST NVD
NVD statusNVD modified after enrichment
Core structured fields are present and their contributing authorities are shown above.
Material change intelligence
View recent updates ↗What changed after publication
No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.
Technical terms and abbreviations used in this report
- CVE
- Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
- CVSS
- Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
- EPSS
- Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
- CWE
- Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
- CNA
- CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
- CISA ADP
- Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
- NVD
- National Vulnerability Database: NIST's enrichment service for CVE records.
- CERT / CSIRT
- A computer security incident response team that publishes warnings or coordinates incident response.
- PoC
- Proof of concept: public material that demonstrates or helps reproduce exploitation.
- CSAF
- Common Security Advisory Framework: a machine-readable format for security advisories.
- LoTL
- Living off the land: abuse of legitimate tools or system functions during an attack.