RUSTSEC-2026-0402None▾ SunlitHeap buffer overflow in `CCtx::try_clone` on a multithreaded context
▾ Sunlit zone — Low / medium · no exploitation signal
impact 2.8 · likelihood 0 · exploitation 0
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Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via OSV
Last analysed / modified upstream
CCtx::try_clone (experimental feature, deprecated) copies tables sized
from the context's applied parameters. Starting a multithreaded frame
(zstdmt feature) replaces those parameters with the workers' without
resizing the context's own tables, so after an abandoned single-threaded
frame, the copy wrote up to 512 KiB past a heap allocation, or read past
one. This became reachable with the bundled zstd 1.5.6.
The flaw was corrected by refusing try_clone (and the unsafe
compress_block) once NbWorkers was set on the context.
zstd-safe >= 8.0.0-0, < 8.2.0Upgrade to a patched release:
zstd-safe 8.2.0Connected by shared product, vendor, weakness, or advisory.
RUSTSEC-2026-0406NoneUse-after-free when changing a multithreaded context with an unfinished frame
RUSTSEC-2026-0405NoneOut-of-bounds read with an out-of-range `InBuffer::pos`
RUSTSEC-2026-0404NoneDouble free in `DCtx::try_clone`
RUSTSEC-2026-0403NoneUninitialized memory exposed when streaming decompression of a legacy frame fails
RUSTSEC-2026-0401NoneOut-of-bounds read in `train_from_buffer` when sample sizes overflow
RUSTSEC-2026-0399NoneUse-after-free through `init_using_cdict` and `init_using_ddict`