Update Rust crate rand [SECURITY]

[renovate-bot]

This PR contains the following updates:

Package	Type	Update	Change
rand (source)	dependencies	patch	0.9.3 → 0.9.4
rand (source)	dev-dependencies	minor	0.9.0 → 0.10.0

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Rand is unsound with a custom logger using rand::rng()

GHSA-cq8v-f236-94qc

More information

Details

It has been reported (by @​lopopolo) that the rand library is unsound (i.e. that safe code using the public API can cause Undefined Behaviour) when all the following conditions are met:

• The log and thread_rng features are enabled
• A custom logger is defined
• The custom logger accesses rand::rng() (previously rand::thread_rng()) and calls any TryRng (previously RngCore) methods on ThreadRng
• The ThreadRng (attempts to) reseed while called from the custom logger (this happens every 64 kB of generated data)
• Trace-level logging is enabled or warn-level logging is enabled and the random source (the getrandom crate) is unable to provide a new seed

TryRng (previously RngCore) methods for ThreadRng use unsafe code to cast *mut BlockRng<ReseedingCore> to &mut BlockRng<ReseedingCore>. When all the above conditions are met this results in an aliased mutable reference, violating the Stacked Borrows rules. Miri is able to detect this violation in sample code. Since construction of aliased mutable references is Undefined Behaviour, the behaviour of optimized builds is hard to predict.

Severity

Low

References

• https://github.com/rust-random/rand/pull/1763
• https://rustsec.org/advisories/RUSTSEC-2026-0097.html
• https://github.com/advisories/GHSA-cq8v-f236-94qc

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

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Release Notes

rust-random/rand (rand)

v0.9.4

Compare Source

Fixes

• Fix doc build (#&rust-lang/rust#8203;1766)

Full Changelog: rust-random/rand@0.9.3...0.9.4

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[rust-log-analyzer]

The job tidy failed! Check out the build log: (web) (plain enhanced) (plain)

Click to see the possible cause of the failure (guessed by this bot)

#14 4.305 Building wheels for collected packages: reuse
#14 4.306   Building wheel for reuse (pyproject.toml): started
#14 4.534   Building wheel for reuse (pyproject.toml): finished with status 'done'
#14 4.536   Created wheel for reuse: filename=reuse-4.0.3-cp310-cp310-manylinux_2_35_x86_64.whl size=132857 sha256=6a78a69541e3df9c7c106367722bab90241125ee6b7cdb81c5e40637268f85a9
#14 4.536   Stored in directory: /tmp/pip-ephem-wheel-cache-38tdit_k/wheels/3d/8d/0a/e0fc6aba4494b28a967ab5eaf951c121d9c677958714e34532
#14 4.539 Successfully built reuse
#14 4.539 Installing collected packages: boolean-py, binaryornot, tomlkit, reuse, python-debian, markupsafe, license-expression, jinja2, chardet, attrs
#14 4.958 Successfully installed attrs-23.2.0 binaryornot-0.4.4 boolean-py-4.0 chardet-5.2.0 jinja2-3.1.4 license-expression-30.3.0 markupsafe-2.1.5 python-debian-0.1.49 reuse-4.0.3 tomlkit-0.13.0
#14 4.959 WARNING: Running pip as the 'root' user can result in broken permissions and conflicting behaviour with the system package manager. It is recommended to use a virtual environment instead: https://pip.pypa.io/warnings/venv
#14 5.614 Collecting virtualenv
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[TIMING:end] tool::Tidy { compiler: Compiler { stage: 0, host: x86_64-unknown-linux-gnu, forced_compiler: false }, target: x86_64-unknown-linux-gnu } -- 0.000
fmt check
fmt: checked 7135 files
tidy check
tidy [deps]: duplicate package `rand_core` is not allowed for the standard library
tidy [deps]: FAIL
tidy [rustdoc_json (src)]: `rustdoc-json-types` modified, checking format version
tidy: Skipping binary file check, read-only filesystem
removing old virtual environment
creating virtual environment at '/checkout/obj/build/venv' using 'python3.10' and 'venv'
creating virtual environment at '/checkout/obj/build/venv' using 'python3.10' and 'virtualenv'
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Running eslint on rustdoc JS files
info: ES-Check: checking 7 files...
info: ✓ ES-Check passed! All files are ES10 compatible.
typechecking javascript files
tidy: The following check failed: deps
Command `/checkout/obj/build/x86_64-unknown-linux-gnu/stage1-tools-bin/rust-tidy --root-path=/checkout --cargo-path=/checkout/obj/build/x86_64-unknown-linux-gnu/stage0/bin/cargo --output-dir=/checkout/obj/build --concurrency=4 --npm-path=/node/bin/yarn --ci=true --extra-checks=py,cpp,js,spellcheck` failed with exit code 1
Created at: src/bootstrap/src/core/build_steps/tool.rs:1605:23
Executed at: src/bootstrap/src/core/build_steps/test.rs:1660:29

Command has failed. Rerun with -v to see more details.
Bootstrap failed while executing `test src/tools/tidy tidyselftest --extra-checks=py,cpp,js,spellcheck`
Currently active steps:
test::Tidy {  } at src/bootstrap/src/core/build_steps/test.rs:1582
Build completed unsuccessfully in 0:02:52
  local time: Thu Aug  6 05:29:30 UTC 2026