Description
Successfully using libcurl to do a transfer over a specific HTTP proxy (`proxyA`) with **Digest** authentication and then changing the proxy host to a second one (`proxyB`) for a second transfer, reusing the same handle, makes libcurl wrongly pass on the `Proxy-Authorization:` header field meant for `proxyA`, to `proxyB`.
Affected products
haxx: curl
References5
- curl.se/docs/CVE-2026-7168.html PatchVendor Advisory
- curl.se/docs/CVE-2026-7168.json Vendor Advisory
- www.openwall.com/lists/oss-security/2026/04/29/14 Mailing ListPatch
- hackerone.com/reports/3697719 ExploitIssue Tracking
- hackerone.com/reports/3697719 ExploitIssue Tracking
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
- 0% percentile: 41 · as of 14 November 2026
- CWE
- CWE-294
Could this be exploited in your environment?
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