CVE-2021-27212

CWE-617 — Reachable AssertionCWE-400 — Uncontrolled Resource Consumption10 documents8 sources
Severity
7.5HIGH
EPSS
22.2%
top 4.20%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
2
Openldap OpenldapDebian Debian Linux
Timeline
PublishedFeb 14
Latest updateAug 24

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.

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitability: 3.9 | Impact: 3.6

Affected Packages3 packages

▶Debianopenldap< 2.4.57+dfsg-2+3
▶Ubuntuopenldap< 2.4.31-1+nmu2ubuntu8.5+esm8
▶NVDopenldap/openldap2.4.57+2

Also affects: Debian Linux 10.0, 9.0

Patches

Patch: git.openldap.org ↗Patch: git.openldap.org ↗Patch: git.openldap.org ↗

🔴Vulnerability Details

4
OSV
openldap vulnerabilities↗2025-08-24
▶
GHSA
GHSA-274h-c788-hf3c: In OpenLDAP through 2↗2022-05-24
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CVEList
CVE-2021-27212: In OpenLDAP through 2↗2021-02-14
▶
OSV
CVE-2021-27212: In OpenLDAP through 2↗2021-02-14
▶

📋Vendor Advisories

5
Ubuntu
OpenLDAP vulnerabilities↗2025-08-24
▶
Ubuntu
OpenLDAP vulnerability↗2021-02-22
▶
Red Hat
openldap: Assertion failure in slapd in the issuerAndThisUpdateCheck function↗2021-02-14
▶
Microsoft
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 e↗2021-02-09
▶
Debian
CVE-2021-27212: openldap - In OpenLDAP through 2.4.57 and 2.5.x through 2.5.1alpha, an assertion failure in...↗2021
▶