Security readout for executives and security teams
This is an old denial-of-service issue affecting Ascend ISDN dial-up environments using Multilink PPP before version 4.6. A remote attacker could abuse spoofed endpoint identification to disrupt service. Business impact is mainly availability for legacy dial-up connectivity, not data theft based on the provided sources. Exposure is likely limited to legacy Ascend ISDN dial-up infrastructure using Multilink PPP, especially systems running software earlier than 4.6. Modern internet-facing systems are unlikely to be affected unless this legacy access path remains in service. Prioritize based on whether legacy ISDN dial-up is still operational. If present, address during legacy-access risk reduction because the impact is service disruption. If absent, track as not applicable with evidence. Mitigation focus: Inventory Ascend ISDN dial-up systems and identify Multilink PPP usage.; Upgrade or replace Ascend software earlier than 4.6 where vendor guidance confirms applicability.; Disable exposed ISDN Multilink PPP services that no longer have a business requirement..
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-1999-1203 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
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.