Critical 9.8Published Mar 29, 2023

CVE-2023-27533A vulnerability in input validation exists in curl <8.0 during communication using the TELNET protocol may allow an attacker to pass on maliciously crafted user name and "telnet options" during serve…

Updated under an hour ago (Oct 28, 2026, 2:10 AM ET)

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It affects Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP and 11 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

A vulnerability in input validation exists in curl <8.0 during communication using the TELNET protocol may allow an attacker to pass on maliciously crafted user name and "telnet options" during server negotiation. The lack of proper input scrubbing allows an attacker to send content or perform option negotiation without the application's intent. This vulnerability could be exploited if an application allows user input, thereby enabling attackers to execute arbitrary code on the system.

CVSS: 9.8 CRITICAL (v3.1, CISA ADP)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness (CWE): CWE-75
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: hackerone
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
haxx curl haxx:curl	from 7.0.0 through 7.881	NVD
fedoraproject fedora fedoraproject:fedora	36	NVD
netapp active_iq_unified_manager netapp:active_iq_unified_manager	all versions	NVD
netapp clustered_data_ontap netapp:clustered_data_ontap	9.0	NVD
netapp h300s_firmware netapp:h300s_firmware	all versions	NVD
netapp h500s_firmware netapp:h500s_firmware	all versions	NVD
netapp h700s_firmware netapp:h700s_firmware	all versions	NVD
1–10 of 12

References

References

https://hackerone.com/reports/1891474	exploit, third-party-advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/36NBD5YLJXXEDZLDGNFCERWRYJQ6LAQW/	vendor-advisory, mailing-list, third-party-advisory
https://security.netapp.com/advisory/ntap-20230420-0011/	third-party-advisory
https://lists.debian.org/debian-lts-announce/2023/04/msg00025.html	mailing-list
https://security.gentoo.org/glsa/202310-12	vendor-advisory, third-party-advisory
https://cert-portal.siemens.com/productcert/html/ssa-398330.html
https://cert-portal.siemens.com/productcert/html/ssa-943925.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.