GHSA-wrw7-89jp-8q8g — glib
Fix: gtk-rs/gtk-rs-core#1343GHSA-wrw7-89jp-8q8g is a security vulnerability in glib. A fix is available for glib — see the affected versions and patch details below.
Unsoundness in `Iterator` and `DoubleEndedIterator` impls for `glib::VariantStrIter`
Real-World Exposure
glibReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects crates.io packages — download data is not available via public APIs for these ecosystems.
Description
The VariantStrIter::impl_get function (called internally by implementations of the Iterator and DoubleEndedIterator traits for this type) was unsound, resulting in undefined behaviour.
An immutable reference &p to a *mut libc::c_char pointer initialized to NULL was passed as an argument to a C function that that mutates the pointer behind &p in-place (i.e. as an out-argument), which was unsound. After changes in recent versions of the Rust compiler, these unsound writes through &p now seem to be completely disregarded when building the glib crate with optimizations.
This subsequently caused all calls of VariantStrIter::impl_get to violate the safety requirements of the std::ffi::CStr::from_ptr function - which requires its argument to be a valid pointer to a C-style string - resulting in crashes due to NULL pointer dereferences.
This was fixed by passing the out-argument pointer explitly as &mut p instead of &p.
This issue has been present since this code was initially added in glib v0.15.0. The mismatch in mutability was likely missed (and not raised as an error by the compiler) because the C function wrapped by VariantStrIter::impl_get is variadic (glib_sys::g_variant_get_child), and the pointer in question is one of the variadic arguments.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | glib | ≥ 0.15.0&&< 0.20.0 | 0.20.0cargo update -p glib --precise 0.20.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for glib, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update glib to 0.20.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-wrw7-89jp-8q8g is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-wrw7-89jp-8q8g can be triaged on real exposure rather than presence alone.
Tailored to GHSA-wrw7-89jp-8q8g. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-wrw7-89jp-8q8g in your dependencies?
O3 Security finds GHSA-wrw7-89jp-8q8g across crates.io dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.