High 7.5Published Jan 25, 2021

CVE-2020-36221An integer underflow was discovered in OpenLDAP before 2.4.57 leading to slapd crashes in the Certificate Exact Assertion processing, resulting in denial of service (schema_init.c serialNumberAndIssu…

Updated under an hour ago (Oct 26, 2026, 1:10 PM ET)

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It affects Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP and 6 other products. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP

Exploited in the last 30 days

An integer underflow was discovered in OpenLDAP before 2.4.57 leading to slapd crashes in the Certificate Exact Assertion processing, resulting in denial of service (schema_init.c serialNumberAndIssuerCheck).

CVSS: 7.5 HIGH (v3.1, NVD)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): Not given
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: mitre
NVD analysis: Modified
Record last updated: Oct 14, 2026
First seen by InfoSec Signals: Oct 14, 2026

Affected products

Affected products

Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP siemens:simatic_s7_1500_cpu_1518_4_pn_dp_mfp (from the name)	from V3.1.0 before V3.1.5	CISA ADP
Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP siemens:simatic_s7_1500_cpu_1518f_4_pn_dp_mfp (from the name)	from V3.1.0 before V3.1.5	CISA ADP
Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP siemens:siplus_s7_1500_cpu_1518_4_pn_dp_mfp (from the name)	from V3.1.0 before V3.1.5	CISA ADP
openldap openldap openldap:openldap	before 2.4.57	NVD
debian debian_linux debian:debian_linux	9.0; 10.0	NVD
apple mac_os_x apple:mac_os_x	from 10.14.0 before 10.14.6; 10.14.6; 10.14.6; 10.14.6; 10.14.6; 10.14.6; 10.14.6; 10.14.6; and 10 more ranges	NVD
apple macos apple:macos	from 11.1 before 11.4	NVD

References

References

https://bugs.openldap.org/show_bug.cgi?id=9404	x-refsource-misc, issue-tracking, vendor-advisory
https://git.openldap.org/openldap/openldap/-/commit/38ac838e4150c626bbfa0082b7e2cf3a2bb4df31	x-refsource-misc, patch, vendor-advisory
https://bugs.openldap.org/show_bug.cgi?id=9424	x-refsource-misc, issue-tracking, vendor-advisory
https://git.openldap.org/openldap/openldap/-/commit/58c1748e81c843c5b6e61648d2a4d1d82b47e842	x-refsource-misc, patch, vendor-advisory
https://git.openldap.org/openldap/openldap/-/tags/OPENLDAP_REL_ENG_2_4_57	x-refsource-misc, release-notes, vendor-advisory
https://lists.debian.org/debian-lts-announce/2021/02/msg00005.html	mailing-list, x-refsource-mlist, third-party-advisory
https://www.debian.org/security/2021/dsa-4845	vendor-advisory, x-refsource-debian, third-party-advisory
https://security.netapp.com/advisory/ntap-20210226-0002/	x-refsource-confirm, third-party-advisory
https://support.apple.com/kb/HT212529	x-refsource-confirm, third-party-advisory
https://support.apple.com/kb/HT212531	x-refsource-confirm, third-party-advisory
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The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.