{"id":"CVE-2026-53600","state":"PUBLISHED","title":"async-tar PAX extension-header desync enables tar entry/content smuggling","description":"async-tar is a tar archive reading/writing library for async Rust. Prior to version 0.6.1, async-tar mis-applies a buffered PAX size extension to an intermediary extension header (a GNU longname L, a GNU longlink K, or a PAX x/g header) instead of to the next file entry. POSIX requires a PAX extended-header record set to describe the next file entry, never an intervening extension header. Because poll_next_raw (src/archive.rs) threads the buffered PAX records into the size computation of whatever raw header it reads next — and that header can be an intermediary L — the stream cursor is advanced by an attacker-chosen amount when the L body is consumed. The parser then desyncs relative to a POSIX-correct tar parser (e.g. GNU tar), reading subsequent bytes at the wrong block boundary. This issue has been patched in version 0.6.1.","publishedAt":"2026-09-02T16:10:27.461Z","updatedAt":"2026-09-02T18:57:48.269Z","severity":{"score":6.3,"label":"Medium","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["dignifiedquire async-tar"],"affected":[{"vendor":"dignifiedquire","product":"async-tar","versions":[{"version":"< 0.6.1","status":"affected"}]}],"references":["https://github.com/dignifiedquire/async-tar/security/advisories/GHSA-35rm-7j9c-2f7m","https://github.com/dignifiedquire/async-tar/releases/tag/v0.6.1"],"weaknesses":["CWE-20","CWE-843"],"ingestedAt":"2026-10-29T20:12:16.098Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/53xxx/CVE-2026-53600.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-53600","state":"PUBLISHED","datePublished":"2026-09-02T16:10:27.461Z","dateUpdated":"2026-09-02T18:57:48.269Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-06-09T19:39:52.404Z"},"containers":{"cna":{"title":"async-tar PAX extension-header desync enables tar entry/content smuggling","descriptions":[{"lang":"en","value":"async-tar is a tar archive reading/writing library for async Rust. Prior to version 0.6.1, async-tar mis-applies a buffered PAX size extension to an intermediary extension header (a GNU longname L, a GNU longlink K, or a PAX x/g header) instead of to the next file entry. POSIX requires a PAX extended-header record set to describe the next file entry, never an intervening extension header. Because poll_next_raw (src/archive.rs) threads the buffered PAX records into the size computation of whatever raw header it reads next — and that header can be an intermediary L — the stream cursor is advanced by an attacker-chosen amount when the L body is consumed. The parser then desyncs relative to a POSIX-correct tar parser (e.g. GNU tar), reading subsequent bytes at the wrong block boundary. This issue has been patched in version 0.6.1."}],"affected":[{"vendor":"dignifiedquire","product":"async-tar","versions":[{"version":"< 0.6.1","status":"affected"}]}],"references":[{"url":"https://github.com/dignifiedquire/async-tar/security/advisories/GHSA-35rm-7j9c-2f7m","name":"https://github.com/dignifiedquire/async-tar/security/advisories/GHSA-35rm-7j9c-2f7m","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/dignifiedquire/async-tar/releases/tag/v0.6.1","name":"https://github.com/dignifiedquire/async-tar/releases/tag/v0.6.1","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"PRESENT","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"LOW","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":6.3,"baseSeverity":"MEDIUM","vectorString":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N","version":"4.0"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-20","lang":"en","description":"CWE-20: Improper Input Validation","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-843","lang":"en","description":"CWE-843: Access of Resource Using Incompatible Type ('Type Confusion')","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-09-02T16:10:27.461Z"},"source":{"advisory":"GHSA-35rm-7j9c-2f7m","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/dignifiedquire/async-tar/security/advisories/GHSA-35rm-7j9c-2f7m","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-09-02T18:57:40.791866Z","id":"CVE-2026-53600","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-09-02T18:57:48.269Z"}}]}}}