Security readout for executives and security teams
Plain-English summary
CVE-2023-35698 lets a remote attacker tell whether FTP usernames are valid on a SICK ICR890-4 because failed login responses differ. This is not a takeover by itself, but it can reduce guesswork for later password attacks against industrial equipment.
Executive priority
Treat as a medium-priority industrial control exposure issue. Prioritize devices reachable beyond trusted management networks, because username discovery can make later credential attacks easier even though this CVE alone does not alter systems or disrupt availability.
Technical view
The issue is CWE-204 Observable Response Discrepancy in the SICK ICR890-4 FTP server. The CVSS 3.1 score is 5.3: network-reachable, low complexity, no privileges or user interaction required, with limited confidentiality impact and no stated integrity or availability impact.
Likely exposure
Exposure is most relevant where SICK ICR890-4 devices have FTP reachable from untrusted networks, shared operations networks, or poorly segmented remote-access paths. The bundle lists the affected product but does not provide fixed-version or deployment prevalence details.
Exploitation context
The provided sources do not state active exploitation, and the CVE is not marked KEV. The practical risk is username enumeration that can support follow-on credential guessing or targeted access attempts if FTP remains reachable.
Researcher notes
Evidence supports username enumeration through failed FTP login response differences. The bundle does not name a patch, fixed version, workaround, or exploit activity. Avoid overstating impact beyond limited confidentiality and follow-on attack enablement.
Mitigation direction
- Review SICK PSIRT and advisory SCA-2023-0006 for vendor remediation guidance.
- Restrict FTP access to trusted management hosts and networks only.
- Block external or unnecessary network paths to the device FTP service.
- Monitor failed FTP authentication patterns for enumeration-like activity.
- Use strong, unique credentials for device accounts.
Validation and detection
- Inventory SICK ICR890-4 devices and confirm whether FTP is enabled.
- Check whether FTP is reachable from untrusted or non-management networks.
- Compare device status against SICK advisory SCA-2023-0006.
- Review authentication logs for repeated failed FTP login attempts.
- Confirm segmentation controls limit management access to approved hosts.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-204: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2023-35698 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 5.3 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N3.91.4Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
5.3MediumVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://sick.com/psirtCVE reference · issue-tracking
- https://sick.com/.well-known/csaf/white/2023/sca-2023-0006.pdfCVE reference · vendor-advisory
- https://sick.com/.well-known/csaf/white/2023/sca-2023-0006.jsonCVE reference · x_csaf
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Observable Response Discrepancy
Observable Response Discrepancy represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.