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`.
CVSS Details
- CVSS 3.1 Base Score: 9.1
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alpine Linux | — | Upgrade curl | Jul 6, 2026 | Jul 3, 2026 |
| Ibm Aix | — | Apply the fix or workaround for curl_advisory11 | Jul 28, 2026 | Jul 28, 2026 |
| Redhat_linux | — | No solution existsUpgrade curl-minimal-debuginfoUpgrade curl-debugsourceUpgrade libcurlUpgrade libcurl-minimal-debuginfoUpgrade curl-debuginfoUpgrade curl-minimalUpgrade libcurl-develUpgrade libcurl-debuginfoUpgrade curlUpgrade libcurl-minimal | Aug 4, 2026 | Jul 3, 2026 |
| Rocky_linux | — | Upgrade libcurl-minimalUpgrade libcurlUpgrade curlUpgrade libcurl-develUpgrade curl-debugsourceUpgrade curl-debuginfoUpgrade libcurl-minimal-debuginfoUpgrade libcurl-debuginfo | Aug 20, 2026 | Aug 17, 2026 |
| Ubuntu | — | Upgrade libcurl3 (Ubuntu Pro)Upgrade libcurl3-gnutls (Ubuntu Pro)Upgrade libcurl3-gnutlsUpgrade libcurl3-nss (Ubuntu Pro)Upgrade libcurl3t64-gnutlsUpgrade curl (Ubuntu Pro)Upgrade libcurl4-nss-dev (Ubuntu Pro)Upgrade libcurl4Upgrade libcurl4-gnutls-devUpgrade libcurl4-gnutls-dev (Ubuntu Pro)Upgrade libcurl4 (Ubuntu Pro)Upgrade libcurl3-nssUpgrade libcurl4t64Upgrade libcurl4-openssl-dev (Ubuntu Pro)Upgrade libcurl4-openssl-devUpgrade libcurl4-nss-devUpgrade curl | Jul 1, 2026 | Jun 30, 2026 |
| Vmware Photon_os | — | Use 'tdnf update' to upgrade all packages to the latest version. | Aug 10, 2026 | Jul 3, 2026 |
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