Description
curl supports the `-t` command line option, known as `CURLOPT_TELNETOPTIONS`in libcurl. This rarely used option is used to send variable=content pairs toTELNET servers.Due to flaw in the option parser for sending `NEW_ENV` variables, libcurlcould be made to pass on uninitialized data from a stack based buffer to theserver. Therefore potentially revealing sensitive internal information to theserver using a clear-text network protocol.This could happen because curl did not call and use sscanf() correctly whenparsing the string provided by the application.
Affected products
haxx: curl; fedoraproject: fedora; netapp: cloud backup; netapp: clustered data ontap; netapp: hci management node; netapp: solidfire; apple: mac os x; apple: macos; oracle: mysql server; oracle: peoplesoft enterprise peopletools; siemens: sinec infrastructure network services; siemens: sinema remote connect server; netapp: h300s firmware; netapp: h300s; netapp: h500s firmware
References10
- cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf PatchThird Party Advisory
- hackerone.com/reports/1223882 ExploitIssue TrackingPatchThird Party Advisory
- www.oracle.com/security-alerts/cpujan2022.html PatchThird Party Advisory
- www.oracle.com/security-alerts/cpuoct2021.html PatchThird Party Advisory
- cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf PatchThird Party Advisory
- hackerone.com/reports/1223882 ExploitIssue TrackingPatchThird Party Advisory
- www.oracle.com/security-alerts/cpujan2022.html PatchThird Party Advisory
- www.oracle.com/security-alerts/cpuoct2021.html PatchThird Party Advisory
- seclists.org/fulldisclosure/2021/Sep/39 Mailing ListThird Party Advisory
- seclists.org/fulldisclosure/2021/Sep/40 Mailing ListThird Party Advisory
Metrics
- CVSS 3.1
-
5.3
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - EPSS — exploit probability
- 5% percentile: 93 · as of 4 November 2026
- CWE
- CWE-200CWE-908
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