Description
When reusing a libcurl handle for sequential transfers driven by environment-variable proxy configuration, libcurl fails to clear the proxy authentication state between requests. Specifically, if the initial transfer authenticates against `proxyA` using Digest auth, a subsequent transfer routed through `proxyB` erroneously leaks the `Proxy-Authorization:` header intended solely for `proxyA`.
References
https://curl.se/docs/CVE-2026-8927.html
https://curl.se/docs/CVE-2026-8927.json
https://hackerone.com/reports/3744543
https://hackerone.com/reports/3744543
CVSS impact metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
9.1 · Critical
Information
Source identifier
2499f714-1537-4658-8207-48ae4bb9eae9
Vulnerability status
Modified
Published
2026-07-03T07:16:25.123Z
3 months agoLast modified
2026-09-15T07:16:33.157Z
3 weeks ago