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AnthropicGHSA-9pwq-gcrx-wghh

Use-After-Free in OwnedView via Unsound 'static Lifetime Promotion in Deref

Medium5.9CVE-2026-55406 · Published Jul 1, 2026

A soundness bug in `buffa`'s `OwnedView<V>` allowed safe Rust code to trigger a use-after-free. The `OwnedView::decode` constructor transmuted a borrowed slice to `&'static [u8]`, and the `Deref` implementation exposed the promoted `'static` lifetime on borrowed view fields (such as `&'static str` and `&'static [u8]`) to callers. Because these references appeared to be `'static`, the borrow checker permitted them to outlive the `OwnedView`; once the `OwnedView` was dropped and its backing buffer freed, those references became dangling, enabling memory corruption, information disclosure of freed heap contents, and cross-thread misuse — all without any `unsafe` code in the calling application. Users are advised to update to the latest patched version of buffa. Thank you to hackerone.com/suul for reporting this issue.

GitHub advisory

Affected versions

PackageAffectedFixed in
buffa
crates.io
< 0.7.00.7.0
Details and references
CVSS 4.0
CVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N
Severity from
GitHub (reviewed advisory)
Weakness
CWE-200, CWE-416

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