{"id":"GHSA-3cv2-h65g-fgmm","aliases":["RUSTSEC-2026-0145"],"status":"published","title":"astral-tokio-tar has a PAX Header Desynchronization issue","description":"### Impact\n\nVersions of astral-tokio-tar prior to 0.6.2 contain a PAX header interpretation bug that allows manipulated entries to be made selectively visible or invisible during extraction with astral-tokio-tar versus other tar implementations. An attacker could use this differential to smuggle unexpected files onto a victim's filesystem.\n\n### Details\n\nWhen a tar stream contains multiple \"header\" entries prior to a file entry, astral-tokio-tar applies the PAX header (`x`) to the next entry in the stream, regardless of type. For example, a stream of `x -\u003e L -\u003e file` (PAX, GNU longname, file) would result in `x`'s extensions being applied to `L` rather than to `file`.\n\n[Per POSIX pax](https://pubs.opengroup.org/onlinepubs/9799919799/utilities/pax.html), this is incorrect: a PAX header always applies to a file entry, not any intermediary entries. See the \"pax Header Block\" section for the specific prescription there.\n\nAs a result of this, an attacker can contrive a tar containing a sequence of tar headers such that astral-tokio-tar applies the PAX header's size extension to the next header in sequence, effectively desynchronizing the stream and enabling astral-tokio-tar specific skippage/extraction of members. In other words, a file can be contrived to extract differently on astral-tokio-tar than on other tar parsers.\n\n### Patches\n\nVersions 0.6.2 and newer of astral-tokio-tar address this differential.\n\n### Workarounds\n\nUsers are advised to upgrade to version 0.6.1 or newer to address this advisory.\n\nThere is no workaround other than upgrading. Users should experience no breaking changes as a result of the upgrade.\n\n### Resources\n\n- GHSA-j5gw-2vrg-8fgx is a similar PAX desynchronization bug\n- GHSA-fp55-jw48-c537 is another similar PAX desynchronization bug","severity":{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N","level":"medium","from":"ghsa"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-20","CWE-843"],"published":"2026-05-18T12:00:00Z","modified":"2026-10-12T18:00:08Z","fixes":[{"ecosystem":"crates.io","package":"astral-tokio-tar","fixed_in":["0.6.2"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"crates.io","package":"astral-tokio-tar","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"0.6.1"},{"fixed":"0.6.2"}]}]},{"source":"osv","ecosystem":"crates.io","package":"astral-tokio-tar","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"0.6.2"}]}]},{"source":"osv","ecosystem":"crates.io","package":"astral-tokio-tar","ranges":[{"type":"SEMVER","events":[{"introduced":"0.0.0-0"},{"fixed":"0.6.2"}]}]}],"references":[{"url":"https://github.com/astral-sh/tokio-tar/security/advisories/GHSA-3cv2-h65g-fgmm","tags":["web"]},{"url":"https://rustsec.org/advisories/RUSTSEC-2026-0145.html","tags":["web","advisory"]},{"url":"https://github.com/advisories/GHSA-3cv2-h65g-fgmm"},{"url":"https://github.com/astral-sh/tokio-tar","tags":["package"]},{"url":"https://crates.io/crates/astral-tokio-tar","tags":["package"]},{"url":"https://github.com/astral-sh/tokio-tar/pull/82","tags":["web"]}],"sources":{"ghsa":[{"id":"GHSA-3cv2-h65g-fgmm","title":"astral-tokio-tar has a PAX Header Desynchronization issue","description":"### Impact\n\nVersions of astral-tokio-tar prior to 0.6.2 contain a PAX header interpretation bug that allows manipulated entries to be made selectively visible or invisible during extraction with astral-tokio-tar versus other tar implementations. An attacker could use this differential to smuggle unexpected files onto a victim's filesystem.\n\n### Details\n\nWhen a tar stream contains multiple \"header\" entries prior to a file entry, astral-tokio-tar applies the PAX header (`x`) to the next entry in the stream, regardless of type. For example, a stream of `x -\u003e L -\u003e file` (PAX, GNU longname, file) would result in `x`'s extensions being applied to `L` rather than to `file`.\n\n[Per POSIX pax](https://pubs.opengroup.org/onlinepubs/9799919799/utilities/pax.html), this is incorrect: a PAX header always applies to a file entry, not any intermediary entries. See the \"pax Header Block\" section for the specific prescription there.\n\nAs a result of this, an attacker can contrive a tar containing a sequence of tar headers such that astral-tokio-tar applies the PAX header's size extension to the next header in sequence, effectively desynchronizing the stream and enabling astral-tokio-tar specific skippage/extraction of members. In other words, a file can be contrived to extract differently on astral-tokio-tar than on other tar parsers.\n\n### Patches\n\nVersions 0.6.2 and newer of astral-tokio-tar address this differential.\n\n### Workarounds\n\nUsers are advised to upgrade to version 0.6.1 or newer to address this advisory.\n\nThere is no workaround other than upgrading. Users should experience no breaking changes as a result of the upgrade.\n\n### Resources\n\n- GHSA-j5gw-2vrg-8fgx is a similar PAX desynchronization bug\n- GHSA-fp55-jw48-c537 is another similar PAX desynchronization bug","status":"published","published":"2026-05-29T19:08:23Z","modified":"2026-05-29T19:08:26Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N","level":"medium"}],"cwes":["CWE-20","CWE-843"],"updated_at":"2026-11-02T14:40:14.666177Z"}],"osv":[{"id":"GHSA-3cv2-h65g-fgmm","title":"astral-tokio-tar has a PAX Header Desynchronization issue","description":"### Impact\n\nVersions of astral-tokio-tar prior to 0.6.2 contain a PAX header interpretation bug that allows manipulated entries to be made selectively visible or invisible during extraction with astral-tokio-tar versus other tar implementations. An attacker could use this differential to smuggle unexpected files onto a victim's filesystem.\n\n### Details\n\nWhen a tar stream contains multiple \"header\" entries prior to a file entry, astral-tokio-tar applies the PAX header (`x`) to the next entry in the stream, regardless of type. For example, a stream of `x -\u003e L -\u003e file` (PAX, GNU longname, file) would result in `x`'s extensions being applied to `L` rather than to `file`.\n\n[Per POSIX pax](https://pubs.opengroup.org/onlinepubs/9799919799/utilities/pax.html), this is incorrect: a PAX header always applies to a file entry, not any intermediary entries. See the \"pax Header Block\" section for the specific prescription there.\n\nAs a result of this, an attacker can contrive a tar containing a sequence of tar headers such that astral-tokio-tar applies the PAX header's size extension to the next header in sequence, effectively desynchronizing the stream and enabling astral-tokio-tar specific skippage/extraction of members. In other words, a file can be contrived to extract differently on astral-tokio-tar than on other tar parsers.\n\n### Patches\n\nVersions 0.6.2 and newer of astral-tokio-tar address this differential.\n\n### Workarounds\n\nUsers are advised to upgrade to version 0.6.1 or newer to address this advisory.\n\nThere is no workaround other than upgrading. Users should experience no breaking changes as a result of the upgrade.\n\n### Resources\n\n- GHSA-j5gw-2vrg-8fgx is a similar PAX desynchronization bug\n- GHSA-fp55-jw48-c537 is another similar PAX desynchronization bug","status":"published","published":"2026-05-29T19:08:23Z","modified":"2026-05-29T19:15:14.574456772Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N","level":"medium"}],"cwes":["CWE-20","CWE-843"],"updated_at":"2026-11-02T15:46:35.747385Z"},{"id":"RUSTSEC-2026-0145","title":"PAX Header Desynchronization in astral-tokio-tar","description":"Versions of astral-tokio-tar prior to 0.6.2 contain a PAX header interpretation bug that allows manipulated entries to be made selectively visible or invisible during extraction with astral-tokio-tar versus other tar implementations. An attacker could use this differential to smuggle unexpected files onto a victim's filesystem.","status":"published","published":"2026-05-18T12:00:00Z","modified":"2026-10-12T18:00:08.332832886Z","updated_at":"2026-11-02T15:53:40.430679Z"}]}}