High 7.5Published Aug 4, 2021

CVE-2021-22926libcurl-using applications can ask for a specific client certificate to be used in a transfer.

Updated under an hour ago (Oct 27, 2026, 7:10 PM ET)

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It affects Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP and 21 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

libcurl-using applications can ask for a specific client certificate to be used in a transfer. This is done with the `CURLOPT_SSLCERT` option (`--cert` with the command line tool).When libcurl is built to use the macOS native TLS library Secure Transport, an application can ask for the client certificate by name or with a file name - using the same option. If the name exists as a file, it will be used instead of by name.If the appliction runs with a current working directory that is writable by other users (like `/tmp`), a malicious user can create a file name with the same name as the app wants to use by name, and thereby trick the application to use the file based cert instead of the one referred to by name making libcurl send the wrong client certificate in the TLS connection handshake.

CVSS: 7.5 HIGH (v3.1, CISA ADP)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-840
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 7.33.0 before 7.78.0	NVD
netapp active_iq_unified_manager netapp:active_iq_unified_manager	all versions; all versions	NVD
netapp clustered_data_ontap netapp:clustered_data_ontap	all versions	NVD
netapp hci_management_node netapp:hci_management_node	all versions	NVD
netapp oncommand_insight netapp:oncommand_insight	all versions	NVD
netapp oncommand_workflow_automation netapp:oncommand_workflow_automation	all versions	NVD
netapp snapcenter netapp:snapcenter	all versions	NVD
1–10 of 22

References

References

https://hackerone.com/reports/1234760	exploit, third-party-advisory
https://lists.apache.org/thread.html/r61db8e7dcb56dc000a5387a88f7a473bacec5ee01b9ff3f55308aacc%40%3Cdev.kafka.apache.org%3E	mailing-list, third-party-advisory
https://lists.apache.org/thread.html/r61db8e7dcb56dc000a5387a88f7a473bacec5ee01b9ff3f55308aacc%40%3Cusers.kafka.apache.org%3E	mailing-list, third-party-advisory
https://lists.apache.org/thread.html/rbf4ce74b0d1fa9810dec50ba3ace0caeea677af7c27a97111c06ccb7%40%3Cusers.kafka.apache.org%3E	mailing-list, third-party-advisory
https://lists.apache.org/thread.html/rbf4ce74b0d1fa9810dec50ba3ace0caeea677af7c27a97111c06ccb7%40%3Cdev.kafka.apache.org%3E	mailing-list, third-party-advisory
https://www.oracle.com/security-alerts/cpuoct2021.html	patch, third-party-advisory
https://security.netapp.com/advisory/ntap-20210902-0003/	third-party-advisory
https://www.oracle.com/security-alerts/cpujan2022.html	patch, third-party-advisory
https://security.netapp.com/advisory/ntap-20211022-0003/	third-party-advisory
https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf	patch, third-party-advisory
1–10 of 13

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.