{"id":"CVE-2026-53600","aliases":["GHSA-35rm-7j9c-2f7m"],"url":"https://o3.security/vulnerability/CVE-2026-53600","summary":"async-tar PAX extension-header desync enables tar entry/content smuggling","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.","published":"2026-09-02T16:10:27.461Z","modified":"2026-09-11T03:48:26.723139435Z","cvss":null,"epss":{"score":0.00324,"percentile":0.25497,"asOf":"2026-09-17"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"crates.io","name":"async-tar","fixedVersion":"0.6.1"}],"fix":null,"references":[{"type":"WEB","url":"https://github.com/dignifiedquire/async-tar/releases/tag/v0.6.1"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53600.json"},{"type":"ADVISORY","url":"https://github.com/dignifiedquire/async-tar/security/advisories/GHSA-35rm-7j9c-2f7m"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-53600"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-11T03:48:26.723139435Z"}}