Relationships

CWE entries form a directed graph via ChildOf, ParentOf, PeerOf, CanPrecede, and CanFollow edges. cwe.cr exposes both the raw edges and resolved-Weakness helpers.

Direct relationships

CWE.parents_of(79)  # => [CWE-74]
CWE.children_of(79) # => [CWE-80, CWE-81, CWE-83, CWE-84, CWE-85, CWE-86, CWE-87]

parents_of walks ChildOf edges from the given id, deduplicated across views. children_of is the inverse, served from a pre-built index — it's O(children), not O(catalog).

Transitive closure

CWE.ancestors_of(79)   # => [CWE-74, CWE-707] (nearest first)
CWE.descendants_of(79) # => all variants under CWE-79

max_depth is an optional safety limit (default 32) — the real CWE has chains of length 3-4, so the limit only matters for pathological inputs.

Pillars

A Pillar is the topmost abstraction class (e.g. CWE-707 "Improper Neutralization", CWE-664 "Improper Control of a Resource Through its Lifetime"). pillar_of walks up ChildOf edges until it finds one:

CWE.pillar_of(79).try(&.cwe_id) # => "CWE-707"

If id is already a Pillar, pillar_of returns it unchanged. If the ancestor chain never reaches a Pillar (a few entries top out at a Class), the most distant ancestor is returned instead.

View-filtered walks

CWE catalogs the same edge multiple times — once per view it appears in. The two most common are:

View 1000 — Research Concepts, the comprehensive graph view
View 1003 — Weaknesses for Simplified Mapping of Published Vulnerabilities

To restrict a walk to a single view, pass view_id::

CWE.parents_of(79, view_id: 1000)   # => [CWE-74]
CWE.parents_of(79, view_id: 1003)   # => [CWE-74]
CWE.parents_of(79, view_id: 9999)   # => []
CWE.ancestors_of(79, view_id: 1000) # full Research-view chain

Raw edges

When you need the full edge metadata (nature, ordinal, chain id, source view id), read it off the Weakness directly:

w = CWE.find!(79)
w.parent_relations  # => Array(CWE::Related) with `ChildOf` nature
w.peer_relations    # => `PeerOf` edges
w.can_precede_relations
w.can_follow_relations
w.related_with("ChildOf") # generic filter