RUSTSEC-2019-0008: Flaw in string parsing can lead to crashes due to invalid memory access.

What to do

1. See which version you have: cargo tree -i simd-json (it also shows which of your dependencies pulls it in).
2. Update within your version requirement: cargo update -p simd-json. If the fix is a newer major or minor than your requirement allows, raise it in Cargo.toml (for example simd-json = "0.1.15") or update the dependency that pulls it in.
3. Check again with cargo audit, or paste your Cargo.lock into our Cargo.toml checker.

Details from the advisory

The affected version of this crate did not guard against accessing memory beyond the range of its input data. A pointer cast to read the data into a 256-bit register could lead to a segmentation fault when the end plus the 32 bytes (256 bit) read would overlap into the next page during string parsing.

page   |  ...  page 1  ...  | ... page 2  ... |
data   | x[n * 32 byte]xx__ |                 |
access | ..][ 32 byte ]     |                 |
segflt |               [ 32 | byte ]          |

This allows an attacker to eventually crash a service.

The flaw was corrected by using a padding buffer for the last read from the input. So that we are we never read over the boundary of the input data.

References

• Package: crates.io/crates/simd-json
• Advisory: rustsec.org/advisories/RUSTSEC-2019-0008.html
• Web: github.com/Licenser/simdjson-rs/pull/27

From the RustSec Advisory Database (CC0-1.0) via the OSV export, downloaded Oct 24, 2026. Severity score computed from the published CVSS vector.