Description
curl would wrongly reuse an existing HTTP proxy connection doing CONNECT to a server, even if the new request uses different credentials for the HTTP proxy. The proper behavior is to create or use a separate connection.
Affected products
haxx: curl
References5
- curl.se/docs/CVE-2026-3784.html PatchVendor Advisory
- curl.se/docs/CVE-2026-3784.json Vendor Advisory
- hackerone.com/reports/3584903 ExploitIssue TrackingThird Party Advisory
- www.openwall.com/lists/oss-security/2026/03/11/3 Mailing ListThird Party Advisory
- cert-portal.siemens.com/productcert/html/ssa-253495.html
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 39 · as of 12 November 2026
- CWE
- CWE-305
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