libcurl might in some circumstances reuse the wrong connection when asked to do Negotiate-authenticated ones, even when they are set to use different "services".
libcurl features a pool of recent connections so that subsequent requests can reuse an existing connection to avoid overhead.
When reusing a connection a range of criteria must be met. Due to a logical error in the code, a request that was issued by an application could wrongfully reuse an existing connection to the same server that was authenticated using different services.
CVSS Details
- CVSS 3.1 Base Score: 6.5
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/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 | — | Upgrade libcurl-minimal-debuginfoUpgrade libcurl-develUpgrade curl-debugsourceUpgrade curl-minimal-debuginfoUpgrade curlUpgrade curl-debuginfoUpgrade libcurl-debuginfoUpgrade curl-minimalUpgrade libcurl-minimalNo solution existsUpgrade libcurl | Aug 10, 2026 | Jul 3, 2026 |
| Rocky_linux | — | Upgrade curl-minimalUpgrade libcurl-minimal-debuginfoUpgrade libcurl-minimalUpgrade curl-debugsourceUpgrade libcurl-develUpgrade curl-debuginfoUpgrade libcurlUpgrade curl-minimal-debuginfoUpgrade libcurl-debuginfoUpgrade curl | Sep 28, 2026 | Sep 22, 2026 |
| Ubuntu | — | Upgrade libcurl3-nssUpgrade libcurl4-openssl-dev (Ubuntu Pro)Upgrade libcurl4t64Upgrade libcurl4-nss-dev (Ubuntu Pro)Upgrade libcurl4-nss-devUpgrade libcurl4-gnutls-devUpgrade libcurl4-gnutls-dev (Ubuntu Pro)Upgrade curlUpgrade libcurl4-openssl-devUpgrade libcurl4 (Ubuntu Pro)Upgrade libcurl3t64-gnutlsUpgrade libcurl4Upgrade libcurl3-gnutls (Ubuntu Pro)Upgrade libcurl3-gnutlsUpgrade curl (Ubuntu Pro)Upgrade libcurl3 (Ubuntu Pro)Upgrade libcurl3-nss (Ubuntu Pro) | 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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