CVE-2021-27212

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.

CVSS 3.1

7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS

66% chance of exploitation in the next 30 days; higher than 99% of CVEs (scores of 2026-10-25)

CWE

CWE-617

Published

2021-02-14

Modified

2026-10-14

Record from

the NVD, synced 2026-10-19

Affected

• debian:debian_linux
• openldap:openldap

References

• https://bugs.openldap.org/show_bug.cgi?id=9454
• https://git.openldap.org/openldap/openldap/-/commit/3539fc33212b528c56b716584f2c2994af7c30b0
• https://git.openldap.org/openldap/openldap/-/commit/9badb73425a67768c09bcaed1a9c26c684af6c30
• 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

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