RUSTSEC-2026-0395
Use-after-free with `CParameter::StableInBuffer`
- Severity
- Not rated yet
- No source has published a CVSS score yet
- Exploit chance (EPSS)
- —
- No score published
- Known exploited
- No
- Not in CISA's catalog
- Weakness
- —
- Not classified
- Fix
8.2.0- Upgrade zstd-safe to this version or later
Description
With CParameter::StableInBuffer(true) (experimental feature), the C
library keeps a pointer to the input of one streaming call and reads from it
in later calls, including flush_stream and end_stream, which take no
input. An InBuffer only borrows its slice for one call, so safe code could
free it in between, and freed memory was compressed into the frame. The C
library behaves this way since zstd 1.5.4, whether bundled or linked from the
system.
The flaw was corrected by refusing to enable the parameter.
Affected versions
crates.io
| Package | Vulnerable | Fixed in |
|---|---|---|
| zstd-safe | >= 4.1.0, < 8.2.0 |
8.2.0 |
How to fix
Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.
zstd-safe crates.io → 8.2.0
- cargo
cargo update -p zstd-safe --precise 8.2.0
References
Advisories
Packages
Other links
Timeline
- Published
- Last updated by the source
Related advisories
| Advisory | Severity | Why it's related |
|---|---|---|
| RUSTSEC-2026-0406 Use-after-free when changing a multithreaded context with an unfinished frame | Not rated yet | Also affects zstd-safe |
| RUSTSEC-2026-0405 Out-of-bounds read with an out-of-range `InBuffer::pos` | Not rated yet | Also affects zstd-safe |
| RUSTSEC-2026-0404 Double free in `DCtx::try_clone` | Not rated yet | Also affects zstd-safe |
| RUSTSEC-2026-0403 Uninitialized memory exposed when streaming decompression of a legacy frame fails | Not rated yet | Also affects zstd-safe |
| RUSTSEC-2026-0402 Heap buffer overflow in `CCtx::try_clone` on a multithreaded context | Not rated yet | Also affects zstd-safe |
| RUSTSEC-2026-0401 Out-of-bounds read in `train_from_buffer` when sample sizes overflow | Not rated yet | Also affects zstd-safe |
| RUSTSEC-2026-0400 Use-after-free of a dictionary after a one-shot call on a context with an open stream | Not rated yet | Also affects zstd-safe |
| RUSTSEC-2026-0399 Use-after-free through `init_using_cdict` and `init_using_ddict` | Not rated yet | Also affects zstd-safe |
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