{"id":"CVE-2021-27212","title":"In OpenLDAP through 2.4.57 and 2.5.x through 2.5.1alpha, an assertion failure in slapd can occur in the issuerAndThisUpdateCheck function via a crafted packet, resulting in a denial of service (daemon exit) via a short timestamp","summary":"In OpenLDAP through 2.4.57 and 2.5.x through 2.5.1alpha, an assertion failure in slapd can occur in the issuerAndThisUpdateCheck function via a crafted packet, resulting in a denial of service (daemon exit) via a short timestamp. This is…","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-617"],"vendor":"openldap","product":"openldap","affected":["openldap <= 2.4.57","openldap = 2.5.0","openldap = 2.5.1","debian_linux = 9.0","debian_linux = 10.0"],"published":"2021-02-14","updated":"2026-10-14","sourceUpdated":"2026-10-14T12:17:09.847","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2021-27212","references":[{"url":"https://bugs.openldap.org/show_bug.cgi?id=9454","label":"cve@mitre.org"},{"url":"https://git.openldap.org/openldap/openldap/-/commit/3539fc33212b528c56b716584f2c2994af7c30b0","label":"cve@mitre.org"},{"url":"https://git.openldap.org/openldap/openldap/-/commit/9badb73425a67768c09bcaed1a9c26c684af6c30","label":"cve@mitre.org"},{"url":"https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b%40%3Cissues.bookkeeper.apache.org%3E","label":"cve@mitre.org"},{"url":"https://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4%40%3Cissues.bookkeeper.apache.org%3E","label":"cve@mitre.org"},{"url":"https://lists.debian.org/debian-lts-announce/2021/02/msg00035.html","label":"cve@mitre.org"},{"url":"https://security.netapp.com/advisory/ntap-20210319-0005/","label":"cve@mitre.org"},{"url":"https://www.debian.org/security/2021/dsa-4860","label":"cve@mitre.org"},{"url":"https://bugs.openldap.org/show_bug.cgi?id=9454","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://git.openldap.org/openldap/openldap/-/commit/3539fc33212b528c56b716584f2c2994af7c30b0","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://git.openldap.org/openldap/openldap/-/commit/9badb73425a67768c09bcaed1a9c26c684af6c30","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b%40%3Cissues.bookkeeper.apache.org%3E","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4%40%3Cissues.bookkeeper.apache.org%3E","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2021/02/msg00035.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.netapp.com/advisory/ntap-20210319-0005/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.debian.org/security/2021/dsa-4860","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-398330.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}],"tags":["nvd"],"epss":0.63321,"epssPercentile":0.99195,"ingestedAt":"2026-10-14T12:29:10.814Z","slug":"CVE-2021-27212","body":"## Overview\n\nIn OpenLDAP through 2.4.57 and 2.5.x through 2.5.1alpha, an assertion failure in slapd can occur in the issuerAndThisUpdateCheck function via a crafted packet, resulting in a denial of service (daemon exit) via a short timestamp. This is related to schema_init.c and checkTime.\n\n## Affected\n\n- `openldap <= 2.4.57`\n- `openldap = 2.5.0`\n- `openldap = 2.5.1`\n- `debian_linux = 9.0`\n- `debian_linux = 10.0`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":54,"depthScoreParts":{"impact":41.3,"likelihood":12.7,"exploitation":0,"ransomware":0},"changes":[]}