{"id":"CVE-2026-55406","state":"PUBLISHED","title":"Buffa: Use-After-Free in OwnedView via Unsound 'static Lifetime Promotion in Deref","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.","publishedAt":"2026-07-16T15:54:29.511Z","updatedAt":"2026-07-16T16:47:37.717Z","severity":{"score":5.9,"label":"Medium","version":"4.0","vector":"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","source":"GitHub_M"},"assigner":"GitHub_M","products":["anthropics buffa"],"affected":[{"vendor":"anthropics","product":"buffa","versions":[{"version":"< 0.7.0","status":"affected"}]}],"references":["https://github.com/anthropics/buffa/security/advisories/GHSA-9pwq-gcrx-wghh","https://github.com/anthropics/buffa/pull/154","https://github.com/anthropics/buffa/commit/7dcf50a1a40eca6ed8d6c6dd59f4310aa0d68b0e","https://github.com/anthropics/buffa/releases/tag/v0.7.0"],"weaknesses":["CWE-200","CWE-416"],"ingestedAt":"2026-10-29T20:12:24.861Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/55xxx/CVE-2026-55406.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-55406","state":"PUBLISHED","datePublished":"2026-07-16T15:54:29.511Z","dateUpdated":"2026-07-16T16:47:37.717Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-06-16T21:48:43.124Z"},"containers":{"cna":{"title":"Buffa: Use-After-Free in OwnedView via Unsound 'static Lifetime Promotion in Deref","descriptions":[{"lang":"en","value":"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":[{"vendor":"anthropics","product":"buffa","versions":[{"version":"< 0.7.0","status":"affected"}]}],"references":[{"url":"https://github.com/anthropics/buffa/security/advisories/GHSA-9pwq-gcrx-wghh","name":"https://github.com/anthropics/buffa/security/advisories/GHSA-9pwq-gcrx-wghh","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/anthropics/buffa/pull/154","name":"https://github.com/anthropics/buffa/pull/154","tags":["x_refsource_MISC"]},{"url":"https://github.com/anthropics/buffa/commit/7dcf50a1a40eca6ed8d6c6dd59f4310aa0d68b0e","name":"https://github.com/anthropics/buffa/commit/7dcf50a1a40eca6ed8d6c6dd59f4310aa0d68b0e","tags":["x_refsource_MISC"]},{"url":"https://github.com/anthropics/buffa/releases/tag/v0.7.0","name":"https://github.com/anthropics/buffa/releases/tag/v0.7.0","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV4_0":{"attackVector":"LOCAL","attackComplexity":"HIGH","attackRequirements":"PRESENT","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"HIGH","vulnIntegrityImpact":"LOW","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":5.9,"baseSeverity":"MEDIUM","vectorString":"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","version":"4.0"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-200","lang":"en","description":"CWE-200: Exposure of Sensitive Information to an Unauthorized Actor","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-416","lang":"en","description":"CWE-416: Use After Free","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-07-16T15:54:29.511Z"},"source":{"advisory":"GHSA-9pwq-gcrx-wghh","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-07-16T16:47:16.390744Z","id":"CVE-2026-55406","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-07-16T16:47:37.717Z"}}]}}}