Application interruption via unchecked geometry bounds and recursion

Out-of-bounds reads and recursion flaws in OCCT 8.0.0-rc5 allow local users to interrupt applications through crafted IGES or STEP files. Geom2d_BSplineCurve::EvalD0 and MakeBSplineCurveCommon access B-spline pole or knot arrays without sufficient bounds validation, while StepShape_OrientedEdge::EdgeStart recursively follows a self-reference without cycle detection. Reachability requires a consuming application to parse attacker-controlled geometry; the documented outcomes are process crashes or stack exhaustion, while the CNA also reports unintended memory disclosure.