GitHub Advisoryadvisory · crates.io

GHSA-h5x4-m2qf-r4f2 Diesel's SQLite backend has possible UTF-8 corruption

HIGH Published 2026-05-05 Modified 2026-05-05 Official page ↗
Ecosystem
crates.io
Packages
diesel
Severity
High
CVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
Weaknesses
CWE-20
Reviewed
2026-05-05

Affected packages

• crates.io diesel: < 2.3.8 → fixed in 2.3.8

Description

Diesel uses the `sqlite3_value_text` function to receive strings from SQLite while deserializing query results. We misinterpreted the corresponding SQLite documentation that this function always returns a UTF-8 encoded string values as `*const c_char`. Based on that we used `str::from_utf8_unchecked` to construct a Rust string slice without any additional UTF-8 checks in place. It turned out that this function doesn't always return correct UTF-8 strings. For field of the SQLite side storage type `BLOB` this pointer can contain arbitrary bytes, which makes the usage of `str::from_utf8_unchecked` unsound as this violates the safety contract of `str` to only contain valid UTF-8 encoded Strings. Mitigation The preferred mitigation to the outlined problem is to update to a Diesel version 2.3.8 or newer, which includes fixes for the problem. Resolution Diesel now correctly checks whether the provides byte buffer is actually valid UTF-8, instead of relying on SQLite's documentation. This fix is included in the `2.3.8` release.

Related

Weakness · CWE (1)

  • CWE-20 Improper Input Validation weakness

References