Stream: git-wasmtime

Topic: wasmtime / issue #15011 RUSTSEC-2026-0402: Heap buffer ov...

Wasmtime GitHub notifications bot (Oct 27 2026 at 00:13):

github-actions[bot] opened issue #15011:

Heap buffer overflow in CCtx::try_clone on a multithreaded context

Details
Status	unsound
Package	zstd-safe
Version	5.0.2+zstd.1.5.2
URL	https://github.com/gyscos/zstd-rs/commit/682b8b2967cf4aba5cfe2d940d1e381a3e23211a
Date	2026-10-16

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.

See advisory page for additional details.

Wasmtime GitHub notifications bot (Oct 27 2026 at 00:39):

pchickey closed issue #15011:

Heap buffer overflow in CCtx::try_clone on a multithreaded context

Details
Status	unsound
Package	zstd-safe
Version	5.0.2+zstd.1.5.2
URL	https://github.com/gyscos/zstd-rs/commit/682b8b2967cf4aba5cfe2d940d1e381a3e23211a
Date	2026-10-16

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.

See advisory page for additional details.

Last updated: Oct 31 2026 at 23:03 UTC