{"id":"CVE-2026-64613","aliases":["EUVD-2026-46369","GHSA-pmmg-wc48-vjhq"],"status":"published","title":"Data::Buffer::Shared versions before 0.05 for Perl create a world-readable mmap backing file and open it without O_NOFOLLOW","description":"Data::Buffer::Shared versions before 0.05 for Perl create a world-readable mmap backing file and open it without O_NOFOLLOW.\n\nThe segment is created in buf_generic.h with open(path, O_RDWR|O_CREAT|O_EXCL, 0666). O_EXCL blocks a pre-seeded file on create, but the mode is 0666, so under the default umask 022 the file is created mode 0644 (world-readable), and O_NOFOLLOW is absent, so a symlink planted at the path is followed when the segment is attached.\n\nA \"Shared\" segment naturally lives in a shared directory such as /tmp or /dev/shm, where any local user can read the IPC payloads stored in the world-readable segment, and a pre-planted symlink at the path redirects the open to another file.","severity":{"version":"3.1","score":6.2,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"medium","assessor":"adp","from":"cve"},"epss":{"day":"2026-11-11","score":0.00176,"percentile":0.07191,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-59","CWE-732"],"published":"2026-07-21T19:05:49Z","modified":"2026-10-24T19:10:00Z","products":[{"vendor":"egor","product":"data::buffer::shared"}],"references":[{"url":"https://metacpan.org/release/EGOR/Data-Buffer-Shared-0.05/diff/EGOR/Data-Buffer-Shared-0.04#buf_generic.h"},{"url":"https://metacpan.org/release/EGOR/Data-Buffer-Shared-0.05/changes","tags":["release-notes"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64613"},{"url":"https://github.com/advisories/GHSA-pmmg-wc48-vjhq"}],"sources":{"cve":[{"id":"CVE-2026-64613","title":"Data::Buffer::Shared versions before 0.05 for Perl create a world-readable mmap backing file and open it without O_NOFOLLOW","description":"Data::Buffer::Shared versions before 0.05 for Perl create a world-readable mmap backing file and open it without O_NOFOLLOW.\n\nThe segment is created in buf_generic.h with open(path, O_RDWR|O_CREAT|O_EXCL, 0666). O_EXCL blocks a pre-seeded file on create, but the mode is 0666, so under the default umask 022 the file is created mode 0644 (world-readable), and O_NOFOLLOW is absent, so a symlink planted at the path is followed when the segment is attached.\n\nA \"Shared\" segment naturally lives in a shared directory such as /tmp or /dev/shm, where any local user can read the IPC payloads stored in the world-readable segment, and a pre-planted symlink at the path redirects the open to another file.","status":"published","published":"2026-07-21T19:05:49.579Z","modified":"2026-07-23T12:25:36.375Z","cvss":[{"version":"3.1","score":6.2,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"medium","assessor":"adp"}],"cwes":["CWE-732","CWE-59"],"updated_at":"2026-11-02T14:19:58.214427Z"}],"euvd":[{"id":"EUVD-2026-46369","description":"Data::Buffer::Shared versions before 0.05 for Perl create a world-readable mmap backing file and open it without O_NOFOLLOW.\n\nThe segment is created in buf_generic.h with open(path, O_RDWR|O_CREAT|O_EXCL, 0666). O_EXCL blocks a pre-seeded file on create, but the mode is 0666, so under the default umask 022 the file is created mode 0644 (world-readable), and O_NOFOLLOW is absent, so a symlink planted at the path is followed when the segment is attached.\n\nA \"Shared\" segment naturally lives in a shared directory such as /tmp or /dev/shm, where any local user can read the IPC payloads stored in the world-readable segment, and a pre-planted symlink at the path redirects the open to another file.","status":"published","published":"2026-07-21T19:05:49Z","modified":"2026-07-23T12:25:36Z","cvss":[{"version":"3.1","score":6.2,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T18:19:44.433437Z"}],"ghsa":[{"id":"GHSA-pmmg-wc48-vjhq","title":"Data::Buffer::Shared versions before 0.05 for Perl create a world-readable mmap backing file and...","description":"Data::Buffer::Shared versions before 0.05 for Perl create a world-readable mmap backing file and open it without O_NOFOLLOW.\n\nThe segment is created in buf_generic.h with open(path, O_RDWR|O_CREAT|O_EXCL, 0666). O_EXCL blocks a pre-seeded file on create, but the mode is 0666, so under the default umask 022 the file is created mode 0644 (world-readable), and O_NOFOLLOW is absent, so a symlink planted at the path is followed when the segment is attached.\n\nA \"Shared\" segment naturally lives in a shared directory such as /tmp or /dev/shm, where any local user can read the IPC payloads stored in the world-readable segment, and a pre-planted symlink at the path redirects the open to another file.","status":"published","published":"2026-07-21T21:32:41Z","modified":"2026-07-23T15:30:36Z","cvss":[{"version":"3.1","score":6.2,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"medium"}],"cwes":["CWE-59"],"updated_at":"2026-11-02T15:09:42.474156Z"}],"nvd":[{"id":"CVE-2026-64613","description":"Data::Buffer::Shared versions before 0.05 for Perl create a world-readable mmap backing file and open it without O_NOFOLLOW.\n\nThe segment is created in buf_generic.h with open(path, O_RDWR|O_CREAT|O_EXCL, 0666). O_EXCL blocks a pre-seeded file on create, but the mode is 0666, so under the default umask 022 the file is created mode 0644 (world-readable), and O_NOFOLLOW is absent, so a symlink planted at the path is followed when the segment is attached.\n\nA \"Shared\" segment naturally lives in a shared directory such as /tmp or /dev/shm, where any local user can read the IPC payloads stored in the world-readable segment, and a pre-planted symlink at the path redirects the open to another file.","status":"published","published":"2026-07-21T20:17:03.967Z","modified":"2026-10-24T19:10:00.127Z","cvss":[{"version":"3.1","score":6.2,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-59","CWE-732"],"updated_at":"2026-11-02T14:12:31.394335Z"}]}}