CVE-2026-8458

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.

• curl 8.21.0~rc2-1 [trixie] - curl (Minor issue) [bookworm] - curl (Minor issue; needs HTTP Negotiate auth with differing service names) [bullseye] - curl (Minor issue; needs HTTP Negotiate auth with differing service names) https://curl.se/docs/CVE-2026-8458.html Introduced with: https://github.com/curl/curl/commit/97c272e5d173ad5f706443e2477f0a84f0044edd (curl-7_43_0) Fixed by: https://github.com/curl/curl/commit/5e99b73cf441d9c369768b9cd48b5389b9a2503d (rc-8_21_0-1, curl-8_21_0)