CVE-2026-55406 (GCVE-0-2026-55406)
Vulnerability from cvelistv5 – Published: 2026-07-16 15:54 – Updated: 2026-07-16 16:47
VLAI
EPSS
VEX
Title
Buffa: Use-After-Free in OwnedView via Unsound 'static Lifetime Promotion in Deref
Summary
Buffa is a pure-Rust Protocol Buffers implementation with first-class protobuf editions support. Prior to 0.7.0, a soundness bug in the OwnedView<V> type 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, so the borrow checker permitted those references to outlive the OwnedView; once the OwnedView was dropped and its backing buffer freed, the references became dangling, enabling memory corruption, information disclosure of freed heap contents, and cross-thread misuse without any unsafe code in the calling application. This issue is fixed in version 0.7.0.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-16 16:47 UTC
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://github.com/anthropics/buffa/security/advi… | x_refsource_CONFIRM |
| https://github.com/anthropics/buffa/pull/154 | x_refsource_MISC |
| https://github.com/anthropics/buffa/commit/7dcf50… | x_refsource_MISC |
| https://github.com/anthropics/buffa/releases/tag/v0.7.0 | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| anthropics | buffa |
Affected:
< 0.7.0
|
guessed |
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