Security readout for executives and security teams
An old design flaw in the ugidd RPC service on Linux lets an unauthenticated remote user ask the service to translate numeric user IDs into real account names. That gives attackers a way to build a list of valid usernames on a target system, which is useful for follow-on password guessing or targeted phishing, though it is not itself a system compromise. Very limited in modern estates. ugidd shipped with legacy Linux NFS user-mapping packages from the late 1990s and is not present in current distributions. Exposure is realistic only on unmaintained legacy Unix or Linux hosts still running RPC-based ugidd reachable on the network, typically behind an unfiltered portmapper. Low priority. Treat as legacy hygiene: worth confirming during routine asset review, not an incident-response event. Only escalate if inventory discovers reachable ugidd services on production or partner-facing networks. Mitigation focus: Inventory hosts for legacy ugidd or rpc.ugidd processes and disable where found.; Restrict portmapper and RPC ports to trusted management networks via firewall rules.; Migrate any remaining hosts to modern NFS with Kerberos-backed authentication..
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-1999-0656 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
- linux-ugidd(348)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.