Description
A user can tell curl >= 7.20.0 and <= 7.78.0 to require a successful upgrade to TLS when speaking to an IMAP, POP3 or FTP server (`--ssl-reqd` on the command line or`CURLOPT_USE_SSL` set to `CURLUSESSL_CONTROL` or `CURLUSESSL_ALL` withlibcurl). This requirement could be bypassed if the server would return a properly crafted but perfectly legitimate response.This flaw would then make curl silently continue its operations **withoutTLS** contrary to the instructions and expectations, exposing possibly sensitive data in clear text over the network.
Affected products
haxx: curl; debian: debian linux; fedoraproject: fedora; netapp: cloud backup; netapp: clustered data ontap; netapp: oncommand insight; netapp: oncommand workflow automation; netapp: snapcenter; netapp: h300s firmware; netapp: h300s; netapp: h500s firmware; netapp: h500s; netapp: h700s firmware; netapp: h700s; netapp: h300e firmware
References10
- cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf PatchThird Party Advisory
- hackerone.com/reports/1334111 ExploitIssue TrackingPatchThird Party Advisory
- www.oracle.com/security-alerts/cpuapr2022.html PatchThird Party Advisory
- www.oracle.com/security-alerts/cpujul2022.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/1334111 ExploitIssue TrackingPatchThird Party Advisory
- www.oracle.com/security-alerts/cpuapr2022.html PatchThird Party Advisory
- www.oracle.com/security-alerts/cpujul2022.html PatchThird Party Advisory
- www.oracle.com/security-alerts/cpuoct2021.html PatchThird Party Advisory
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - EPSS — exploit probability
- 5% percentile: 92 · as of 4 November 2026
- CWE
- CWE-325CWE-319
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