Security readout for executives and security teams
Plain-English summary
This is an old denial-of-service issue in BisonWare FTP Server 4.1 and earlier. A remote attacker could crash the FTP service by sending malformed input to the FTP PORT command. The sources do not provide a CVSS score, patch details, or evidence of active exploitation.
Executive priority
Treat as a legacy exposure cleanup item unless BisonWare FTP is still reachable. If found in production, prioritize replacement because no supplied source names a patch or durable mitigation.
Technical view
CVE-1999-1156 describes a remote crash condition triggered by a malformed FTP PORT command containing a non-numeric character and many carriage returns. The public record names BisonWare FTP Server 4.1 and earlier. No CWE, CPE, exploit maturity, or vendor remediation detail is provided in the supplied sources.
Likely exposure
Exposure appears limited to organizations still running BisonWare FTP Server 4.1 or earlier, especially if reachable from untrusted networks. The source bundle does not identify affected CPEs or modern downstream products.
Exploitation context
The CVE record supports remote denial of service, but not code execution, privilege escalation, data theft, or active exploitation. It is not listed as KEV in the supplied bundle.
Researcher notes
The evidence is sparse and mostly identifies a malformed-command crash. Avoid assuming broader FTP server impact. Validation should focus on asset/version confirmation and availability telemetry, not reproducing the crash in production.
Mitigation direction
- Check vendor or archive guidance for any available fixed release.
- Retire or replace BisonWare FTP Server if it is still in use.
- Restrict FTP access to trusted networks only.
- Place the service behind firewall or VPN controls where operationally required.
- Monitor FTP service availability and unexpected restarts.
Validation and detection
- Inventory internet-facing and internal FTP services for BisonWare FTP Server.
- Confirm any discovered instance is newer than version 4.1 or decommissioned.
- Review service logs for unexplained FTP crashes or restarts.
- Verify network controls limit FTP exposure to trusted sources.
- Document uncertainty where product version cannot be confirmed.
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.
CVE-1999-1156 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
- bisonware-port-crash(2254)CVE reference · vdb-entry, x_refsource_XF
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.