High 7.5Published Sep 4, 2020

CVE-2020-24659An issue was discovered in GnuTLS before 3.6.15.

Updated under an hour ago (Oct 27, 2026, 7:10 AM 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 issue was discovered in GnuTLS before 3.6.15. A server can trigger a NULL pointer dereference in a TLS 1.3 client if a no_renegotiation alert is sent with unexpected timing, and then an invalid second handshake occurs. The crash happens in the application's error handling path, where the gnutls_deinit function is called after detecting a handshake failure.

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
gnu gnutls gnu:gnutls	before 3.6.15	NVD
fedoraproject fedora fedoraproject:fedora	32; 33	NVD
opensuse leap opensuse:leap	15.1; 15.2	NVD
canonical ubuntu_linux canonical:ubuntu_linux	20.04	NVD

References

References

https://gitlab.com/gnutls/gnutls/-/issues/1071	x-refsource-misc, exploit, issue-tracking, third-party-advisory
https://www.gnutls.org/security-new.html#GNUTLS-SA-2020-09-04	x-refsource-misc, vendor-advisory
https://security.gentoo.org/glsa/202009-01	vendor-advisory, x-refsource-gentoo, third-party-advisory
https://security.netapp.com/advisory/ntap-20200911-0006/	x-refsource-confirm, third-party-advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/62BUAI4FQQLG6VTKRT7SUZPGJJ4NASQ3/	vendor-advisory, x-refsource-fedora
https://usn.ubuntu.com/4491-1/	vendor-advisory, x-refsource-ubuntu, third-party-advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AWN56FDLQQXT2D2YHNI4TYH432TDMQ7N/	vendor-advisory, x-refsource-fedora
http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00054.html	vendor-advisory, x-refsource-suse, mailing-list, third-party-advisory
http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00060.html	vendor-advisory, x-refsource-suse, mailing-list, third-party-advisory
https://cert-portal.siemens.com/productcert/html/ssa-398330.html

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.