Medium severity · published Jul 16, 2026
CVE-2026-55406
Buffa: Use-After-Free in OwnedView via Unsound 'static Lifetime Promotion in Deref
5.9
CVSS
0.2%
EPSS
No
On KEV
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.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 9% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
BU
buffa · anthropics
< 0.7.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-55406
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-55406
github.com
https://github.com/anthropics/buffa/commit/7dcf50a1a40eca6ed8d6c6dd59f4310aa0d68b0e
github.com
https://github.com/anthropics/buffa/pull/154
github.com
https://github.com/anthropics/buffa/releases/tag/v0.7.0
github.com
https://github.com/anthropics/buffa/security/advisories/GHSA-9pwq-gcrx-wghh
More from buffa
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CVE-2026-55407
Buffa: Memory Exhaustion Denial of Service in decode_unknown_field via Unbounded Allocation
