Security readout for executives and security teams
Plain-English summary
Rapid7 Nexpose hardware appliances shipped before June 2017 used an SSH configuration that allowed obsolete algorithms. This can weaken administrative SSH connections and may expose appliance management to man-in-the-middle, downgrade, or decryption attacks.
Executive priority
Prioritize review if affected appliances still exist or SSH management is exposed beyond a tightly controlled admin network. The issue affects management-channel cryptography, but available evidence does not show active exploitation or a CVSS score.
Technical view
The default SSH configuration did not pin desired key exchange and related algorithms. It therefore accepted all algorithms supported by the appliance OpenSSH version, including obsolete choices. The source maps this to CWE-327 and identifies pre-June 2017 Nexpose hardware appliances as affected.
Likely exposure
Exposure is likely limited to organizations that still operate Rapid7 Nexpose hardware appliances shipped before June 2017, especially where SSH management is reachable by administrators or broader networks.
Exploitation context
No KEV listing or provided source states active exploitation. Practical abuse would generally require access to the SSH network path or ability to influence a management connection; the source describes MITM, downgrade, and decryption attack impact.
Researcher notes
The source bundle gives affected product and weakness class but limited remediation detail. Avoid assuming software versions, patches, or exploit status beyond the Rapid7 advisory and CVE record. Validate exposure through asset inventory and SSH algorithm assessment.
Mitigation direction
- Identify any Rapid7 Nexpose hardware appliances shipped before June 2017.
- Review Rapid7’s advisory and current vendor guidance for supported remediation.
- Restrict SSH management access to trusted administrative networks.
- Disable obsolete SSH algorithms only according to vendor-supported guidance.
- Retire or replace unsupported affected appliances.
Validation and detection
- Inventory Nexpose hardware appliances and confirm shipment or deployment dates.
- Review SSH configuration for explicit approved algorithm settings.
- Use authorized configuration assessment tooling to identify accepted SSH algorithms.
- Confirm SSH management exposure is limited to trusted administrative sources.
- Record remediation status against each appliance asset.
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-327: 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-2017-5243 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
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
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 and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://community.rapid7.com/community/nexpose/blog/2017/05/31/r7-2017-13-nexpose-hardware-appliance-ssh-enabled-obsolete-algorithms-cve-2017-5243CVE reference · x_refsource_CONFIRM
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.
Use of a Broken or Risky Cryptographic Algorithm
Use of a Broken or Risky Cryptographic Algorithm represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.