Reference page — cumulative record through Monday, October 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2021-27212

CVE-2021-27212HIGH

n/a n/a — 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…

  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   N   L   N   N  U  N  N  H    7.5   .6611   99.3     —

AFFECTED
  Product  Versions  Fixed
  n/a      n/a –     —

TIMELINE
  Feb 14  Reserved by mitre
  Feb 14  Published (CNA: mitre)
  Oct 14  ENRICHED — CVE-2021-27212. Received CVSS 7.5 and CPE data from NVD.
  Oct 14  EXPLOIT PUBLISHED — CVE-2021-27212. Public exploit reference added.

CWE-617 · CNA: mitre · CVSS v3.1 · 9 references · NVD status: Modified

Description

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 related to schema_init.c and checkTime.

Lifecycle

Complete event history — 4 events, chronological
Date	Event	Detail
February 14, 2021	Reserved	Reserved by mitre
February 14, 2021	Published	Published (CNA: mitre)
October 14, 2026	ENRICHED	ENRICHED — CVE-2021-27212. Received CVSS 7.5 and CPE data from NVD.
October 14, 2026	EXPLOIT PUBLISHED	EXPLOIT PUBLISHED — CVE-2021-27212. Public exploit reference added.

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
n/a	n/a	—	n/a	—

Weaknesses

CWE-617

References (9)

https://bugs.openldap.org/show_bug.cgi?id=9454 [Exploit, Issue Tracking, Vendor Advisory]
https://cert-portal.siemens.com/productcert/html/ssa-398330.html
https://git.openldap.org/openldap/openldap/-/commit/3539fc33212b528c56b716584f2c2994af7c30b0 [Patch, Vendor Advisory]
https://git.openldap.org/openldap/openldap/-/commit/9badb73425a67768c09bcaed1a9c26c684af6c30 [Patch, Vendor Advisory]
https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b%40%3Cissues.bookkeeper.apache.org%3E
https://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4%40%3Cissues.bookkeeper.apache.org%3E
https://lists.debian.org/debian-lts-announce/2021/02/msg00035.html [Mailing List, Third Party Advisory]
https://security.netapp.com/advisory/ntap-20210319-0005/ [Third Party Advisory]
https://www.debian.org/security/2021/dsa-4860 [Third Party Advisory]

Authoritative record: CVE-2021-27212 at cve.org

Weaknesses: CWE-617

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2021-27212 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Monday, October 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.