CVE-2026-55406

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

MEDIUM
5.9
CVSS Score
Published: July 16, 2026 at 03:54 PM UTC
Updated: October 24, 2026 at 08:10 PM UTC
1 product affected across 1 vendorBuffa

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Severity
MEDIUM5.9
Exploit prediction
EPSS 0.2%
SSVC
No known exploit

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 0.7.0
Affected range stops below 0.7.0, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

5.9MEDIUMGitHub_M
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-200CWE-416

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