RUSTSEC-2026-0252
Panic-safety unsoundness in `SplitVec::extend_from_slice` (uninitialized read)
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.
Impact
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.
Fix
Fixed in orx-split-vec 4.0.0, which no longer commits the length before the elements are cloned.
What each source reports
OSV No score
Panic-safety unsoundness in `SplitVec::extend_from_slice` (uninitialized read)
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.
Impact
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.
Fix
Fixed in orx-split-vec 4.0.0, which no longer commits the length before the elements are cloned.
- Record
RUSTSEC-2026-0252- Updated
- 2026-11-02
Affected packages
| Package | Affected | Fixed |
|---|---|---|
orx-split-veccrates.io |
0.0.0-0 up to 4.0.0 | 4.0.0 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
RUSTSEC-2026-0252 is a vulnerability with no CVSS score yet in orx-split-vec, published August 11, 2026. No source lists public exploit code. Fixed in orx-split-vec 4.0.0.