RUSTSEC-2026-0252None▾ SunlitPanic-safety unsoundness in `SplitVec::extend_from_slice` (uninitialized read)
▾ Sunlit zone — Low / medium · no exploitation signal
impact 2.8 · likelihood 0 · exploitation 0
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SplitVec::extend_from_slice increments the logical length self.len before cloning the incoming elements into the reserved slots. If an element's Clone panics mid-fill, unwinding leaves self.len counting slots that were never initialized. A later safe read (get, indexing, iter) then reads one of those uninitialized slots.
This is reachable from safe Rust — a read of uninitialized memory (CWE-908). It is not a double-free: SplitVec has no manual Drop and its elements live in a standard Vec, so the defect is a read, not a free.
A safe read after the panic returns a value built from uninitialized bytes. For a heap-owning element type such as String, the resulting value has garbage length/pointer fields.
Confirmed under Miri. AddressSanitizer stays silent for this class, since the uninitialized bytes are consumed as a non-dereferenced field rather than an invalid load or free.
Fixed in orx-split-vec 4.0.0, which no longer commits the length before the elements are cloned.
orx-split-vec >= 0.0.0-0, < 4.0.0Upgrade to a patched release:
orx-split-vec 4.0.0