{"id":"CVE-2026-39457","aliases":["EUVD-2026-26356","GHSA-gfv8-jx4x-32h7"],"status":"published","title":"Stack overflow via select() file descriptor set overflow","description":"When exchanging data over a socket, libnv uses select(2) to wait for data to arrive.  However, it does not verify whether the provided socket descriptor fits in select(2)'s file descriptor set size limit of FD_SETSIZE (1024).\n\nAn attacker who is able to force a libnv application to allocate large file descriptors, e.g., by opening many descriptors and executing a program which is not careful to close them upon startup, can trigger stack corruption.  If the target application is setuid-root, then this could be used to elevate local privileges.","severity":{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"adp","from":"cve"},"epss":{"day":"2026-11-10","score":0.00151,"percentile":0.04336,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-121"],"published":"2026-04-30T08:01:49Z","modified":"2026-06-17T10:42:07Z","products":[{"vendor":"freebsd","product":"freebsd"}],"references":[{"url":"https://security.freebsd.org/advisories/FreeBSD-SA-26:16.libnv.asc","tags":["vendor-advisory","Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-39457"},{"url":"https://github.com/advisories/GHSA-gfv8-jx4x-32h7"}],"sources":{"cve":[{"id":"CVE-2026-39457","title":"Stack overflow via select() file descriptor set overflow","description":"When exchanging data over a socket, libnv uses select(2) to wait for data to arrive.  However, it does not verify whether the provided socket descriptor fits in select(2)'s file descriptor set size limit of FD_SETSIZE (1024).\n\nAn attacker who is able to force a libnv application to allocate large file descriptors, e.g., by opening many descriptors and executing a program which is not careful to close them upon startup, can trigger stack corruption.  If the target application is setuid-root, then this could be used to elevate local privileges.","status":"published","published":"2026-04-30T08:01:49.015Z","modified":"2026-05-01T03:55:51.194Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"adp"}],"cwes":["CWE-121"],"updated_at":"2026-11-02T14:20:02.662847Z"}],"euvd":[{"id":"EUVD-2026-26356","description":"When exchanging data over a socket, libnv uses select(2) to wait for data to arrive.  However, it does not verify whether the provided socket descriptor fits in select(2)'s file descriptor set size limit of FD_SETSIZE (1024).\n\nAn attacker who is able to force a libnv application to allocate large file descriptors, e.g., by opening many descriptors and executing a program which is not careful to close them upon startup, can trigger stack corruption.  If the target application is setuid-root, then this could be used to elevate local privileges.","status":"published","published":"2026-04-30T08:01:49Z","modified":"2026-05-01T03:55:51Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T19:05:18.723006Z"}],"ghsa":[{"id":"GHSA-gfv8-jx4x-32h7","title":"When exchanging data over a socket, libnv uses select(2) to wait for data to arrive.  However, it...","description":"When exchanging data over a socket, libnv uses select(2) to wait for data to arrive.  However, it does not verify whether the provided socket descriptor fits in select(2)'s file descriptor set size limit of FD_SETSIZE (1024).\n\nAn attacker who is able to force a libnv application to allocate large file descriptors, e.g., by opening many descriptors and executing a program which is not careful to close them upon startup, can trigger stack corruption.  If the target application is setuid-root, then this could be used to elevate local privileges.","status":"published","published":"2026-04-30T09:30:25Z","modified":"2026-04-30T15:31:41Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"cwes":["CWE-121"],"updated_at":"2026-11-02T15:07:52.236911Z"}],"nvd":[{"id":"CVE-2026-39457","description":"When exchanging data over a socket, libnv uses select(2) to wait for data to arrive.  However, it does not verify whether the provided socket descriptor fits in select(2)'s file descriptor set size limit of FD_SETSIZE (1024).\n\nAn attacker who is able to force a libnv application to allocate large file descriptors, e.g., by opening many descriptors and executing a program which is not careful to close them upon startup, can trigger stack corruption.  If the target application is setuid-root, then this could be used to elevate local privileges.","status":"published","published":"2026-04-30T09:16:03.27Z","modified":"2026-06-17T10:42:07.727Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"secondary"}],"cwes":["CWE-121"],"updated_at":"2026-11-02T14:12:16.626888Z"}]}}