CVE-2021-22926 — libcurl-using applications can ask for a specific client certificate to be used in a transfer....
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.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 9.8% (30-day exploitation probability)+14
- Technical severity (high)+6
- CISA SSVC: exploitation "poc"+5
- Automatable exploitation (SSVC)+3
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
- Documented patch — cert-portal.siemens.com (NIST National Vulnerability Database)
- Documented patch — www.oracle.com (NIST National Vulnerability Database)
- Documented patch — www.oracle.com (NIST National Vulnerability Database)
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Haxx Curl, Netapp Active Iq Unified Manager, Netapp Clustered Data Ontap…).
- The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
- Apply the fixed version or the patch documented under Remediation.
- EPSS ahead of 95% of scored CVEs: prioritize it in the patch queue.
- Search available logs for exploit probes matching the vulnerability class (cryptography), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Haxx | Curl | ≥ 7.33.0 and < 7.78.0 | Vulnerable | NIST National Vulnerability Database |
| Netapp | Active Iq Unified Manager | versions not specified by the source | Vulnerable | NIST National Vulnerability Database |
| Netapp | Clustered Data Ontap | versions not specified by the source | Vulnerable | NIST National Vulnerability Database |
| Netapp | H300e Firmware | versions not specified by the source | Vulnerable | NIST National Vulnerability Database |
| Netapp | H300s Firmware | versions not specified by the source | Vulnerable | NIST National Vulnerability Database |
| Netapp | H410s Firmware | versions not specified by the source | Vulnerable | NIST National Vulnerability Database |
| Netapp | H500e Firmware | versions not specified by the source | Vulnerable | NIST National Vulnerability Database |
| Netapp | H500s Firmware | versions not specified by the source | Vulnerable | NIST National Vulnerability Database |
| Netapp | H700e Firmware | versions not specified by the source | Vulnerable | NIST National Vulnerability Database |
| Netapp | H700s Firmware | versions not specified by the source | Vulnerable | NIST National Vulnerability Database |
| Netapp | Hci Management Node | versions not specified by the source | Vulnerable | NIST National Vulnerability Database |
| Netapp | Oncommand Insight | versions not specified by the source | Vulnerable | NIST National Vulnerability Database |
| Netapp | Oncommand Workflow Automation | versions not specified by the source | Vulnerable | NIST National Vulnerability Database |
| Netapp | Snapcenter | versions not specified by the source | Vulnerable | NIST National Vulnerability Database |
| Netapp | Solidfire | versions not specified by the source | Vulnerable | NIST National Vulnerability Database |
| Oracle | Mysql Server | ≥ 5.7.0 and ≤ 5.7.35≥ 8.0.0 and ≤ 8.0.26 | Vulnerable | NIST National Vulnerability Database |
| Oracle | Peoplesoft Enterprise Peopletools | version 8.57version 8.59version 8.58 | Vulnerable | NIST National Vulnerability Database |
| Siemens | Sinec Infrastructure Network Services | < 1.0.1.1 | Vulnerable | NIST National Vulnerability Database |
| Splunk | Universal Forwarder | ≥ 8.2.0 and < 8.2.12≥ 9.0.0 and < 9.0.6version 9.1.0 | Vulnerable | NIST National Vulnerability Database |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 7.5 | CVSS 3.1 | High | 3.9 | 3.6 | nvd@nist.gov via NIST National Vulnerability Database |
| 7.5 | CVSS 3.1 | High | 3.9 | 3.6 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 via NIST National Vulnerability Database |
| 7.5 | CVSS 3.1 | High | — | — | GitHub, Inc. via GitHub Security Advisories |
| 7.5 | CVSS 3.1 | High | — | — | CISA-ADP via CVE Program (cve.org) e CISA ADP |
| 5.0 | CVSS 2.0 | Medium | 10.0 | 2.9 | nvd@nist.gov via NIST National Vulnerability Database |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H (score shown at the top: nvd@nist.gov) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
EPSS over time FIRST
Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 9.82%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
- Check TLS negotiations and unexpected certificates in the component’s traffic.
Timeline
What happened to this CVE, newest first.
- 2026
- SSVC assessment updated
- Record published
- Fix documented
- Affected products added · haxx/curl, netapp/active iq unified manager, netapp/clustered data ontap, netapp/hci management node, netapp/oncommand i
- CVSS changed · 7.5
- Source status changed · → Modified
- Record created in this database
- 2021
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 2× References added · Oct 14, 2026 – Oct 14, 2026
- 1× Official description updated · Oct 14, 2026 – Oct 14, 2026
References
21 on the record
- www.oracle.com/security-alerts/cpuoct2021.html
- www.oracle.com/security-alerts/cpujan2022.html
- cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf
- security.netapp.com/advisory/ntap-20210902-0003
- security.netapp.com/advisory/ntap-20211022-0003
- nvd.nist.gov/vuln/detail/CVE-2021-22926
- security.netapp.com/advisory/ntap-20210902-0003/
- lists.apache.org/thread.html/rbf4ce74b0d1fa9810dec50ba3ace0caeea677af7c27a97111c06ccb7
- hackerone.com/reports/1234760
- lists.apache.org/thread.html/r61db8e7dcb56dc000a5387a88f7a473bacec5ee01b9ff3f55308aacc
- security.netapp.com/advisory/ntap-20211022-0003/
- lists.apache.org/thread.html/rbf4ce74b0d1fa9810dec50ba3ace0caeea677af7c27a97111c06ccb7
- lists.apache.org/thread.html/r61db8e7dcb56dc000a5387a88f7a473bacec5ee01b9ff3f55308aacc
- lists.apache.org/thread.html/rbf4ce74b0d1fa9810dec50ba3ace0caeea677af7c27a97111c06ccb7
- cert-portal.siemens.com/productcert/html/ssa-398330.html
- cert-portal.siemens.com/productcert/html/ssa-389290.html
- security.gentoo.org/glsa/202212-01
- github.com/advisories/GHSA-5xph-62q2-pxff
- lists.apache.org/thread.html/r61db8e7dcb56dc000a5387a88f7a473bacec5ee01b9ff3f55308aacc
- lists.apache.org/thread.html/r61db8e7dcb56dc000a5387a88f7a473bacec5ee01b9ff3f55308aacc
- lists.apache.org/thread.html/rbf4ce74b0d1fa9810dec50ba3ace0caeea677af7c27a97111c06ccb7
Elsewhere on this site
Related CVEs (same products)
- High CVE-2026-83014 Improper Access Control in Oracle Peoplesoft Enterprise Peopletools Sep 15, 2026
- High CVE-2026-83019 Improper Access Control in Oracle Peoplesoft Enterprise Peopletools Sep 15, 2026
- High CVE-2026-83018 Improper Access Control in Oracle Peoplesoft Enterprise Peopletools Sep 15, 2026
- High CVE-2026-83017 Improper Access Control in Oracle Peoplesoft Enterprise Peopletools Sep 15, 2026
- High CVE-2026-83015 Improper Access Control in Oracle Peoplesoft Enterprise Peopletools Sep 15, 2026
- High CVE-2026-83016 Improper Access Control in Oracle Peoplesoft Enterprise Peopletools Sep 15, 2026
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2021-22926 is "libcurl-using applications can ask for a specific client certificate to be used in a transfer....", rated High. It affects Curl (Haxx); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.5 describes technical severity. EPSS 9.82% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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