{"id":"UBUNTU-CVE-2026-53600","details":"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.","modified":"2026-09-16T11:36:38Z","published":"2026-09-02T16:17:00Z","upstream":["CVE-2026-53600"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-53600"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-53600"},{"type":"REPORT","url":"https://github.com/dignifiedquire/async-tar/security/advisories/GHSA-35rm-7j9c-2f7m"},{"type":"REPORT","url":"https://github.com/dignifiedquire/async-tar/releases/tag/v0.6.1"}],"affected":[{"package":{"name":"rust-async-tar","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/rust-async-tar?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.4.2-2"],"ecosystem_specific":{"binaries":[{"binary_version":"0.4.2-2","binary_name":"librust-async-tar-dev"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-53600.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"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"},{"type":"Ubuntu","score":"medium"}]}