What’s Vulnerable › Vulnerabilities
CVE-2021-22926
- Severity: high (CVSS 7.5 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 15.1% probability of exploitation in the next 30 days
- Public exploit or detection template: yes
- Published: 2021-08-05 · updated 2026-10-14
- Weakness: CWE-840
Description
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.
Affected products
- curl: from 7.33.0 before 7.78.0 — fixed in 7.78.0
- Active IQ Unified Manager for VMware vSphere, Linux, and Microsoft Windows: all versions
- Clustered Data ONTAP: all versions
- NetApp H300E Firmware: all versions
- NetApp H300S Firmware: all versions
- NetApp H410S Firmware: all versions
- NetApp H500E Firmware: all versions
- NetApp H500S Firmware: all versions
- NetApp H700E Firmware: all versions
- NetApp H700S Firmware: all versions
- NetApp Hci Management Node: all versions
- OnCommand Insight: all versions
- NetApp OnCommand Workflow Automation: all versions
- NetApp SnapCenter: all versions
- NetApp Solidfire: all versions
- MySQL Server: from 5.7.0 through 5.7.35; from 8.0.0 through 8.0.26
- Oracle Corporation PeopleSoft Enterprise PT PeopleTools: 8.57, 8.58, 8.59
- Siemens Sinec Infrastructure Network Services: before 1.0.1.1 — fixed in 1.0.1.1
- Splunk Universal Forwarder: from 8.2.0 before 8.2.12; from 9.0.0 before 9.0.6; 9.1.0 — fixed in 8.2.12, 9.0.6
How to fix
Upgrade to a fixed version: curl 7.78.0; Siemens Sinec Infrastructure Network Services 1.0.1.1; Splunk Universal Forwarder 8.2.12, 9.0.6. Check the vendor advisory for mitigations.
References
- https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf
- https://hackerone.com/reports/1234760
- https://lists.apache.org/thread.html/r61db8e7dcb56dc000a5387a88f7a473bacec5ee01b9ff3f55308aacc%40%3Cdev.kafka.apache.org%3E
- https://lists.apache.org/thread.html/r61db8e7dcb56dc000a5387a88f7a473bacec5ee01b9ff3f55308aacc%40%3Cusers.kafka.apache.org%3E
- https://lists.apache.org/thread.html/rbf4ce74b0d1fa9810dec50ba3ace0caeea677af7c27a97111c06ccb7%40%3Cdev.kafka.apache.org%3E
- https://lists.apache.org/thread.html/rbf4ce74b0d1fa9810dec50ba3ace0caeea677af7c27a97111c06ccb7%40%3Cusers.kafka.apache.org%3E
- https://security.gentoo.org/glsa/202212-01
- https://security.netapp.com/advisory/ntap-20210902-0003/
- https://security.netapp.com/advisory/ntap-20211022-0003/
- https://www.oracle.com/security-alerts/cpujan2022.html
- https://www.oracle.com/security-alerts/cpuoct2021.html
- https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf
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