Affected: Alpaquita:23: curl, Alpaquita:25: curl, Alpaquita:stream: curl, BellSoft Hardened Containers:stream: curl

Using libcurl, when a custom `Host:` header is first set for an HTTP request and a second request is subsequently done using the same *easy handle* but without the custom `Host:` header set, the second request would use stale information and pass on cookies meant for the first host in the second request. Leak them.

Using libcurl, when a custom `Host:` header is first set for an HTTP request and a second request is subsequently done using the same *easy handle* but without the custom `Host:` header set, the second request would use stale information and pass on cookies meant for the first host in the second request. Leak them.

Affected: openEuler:22.03-LTS-SP4: curl

cURL is a computer software project providing a library (libcurl) and command-line tool (curl) for transferring data using various protocols. Security Fix(es):

A vulnerability exists where a connection requiring TLS incorrectly reuses an existing unencrypted connection from the same connection pool. If an initial transfer is made in clear-text (via IMAP, SMTP, or POP3), a subsequent request to that same host bypasses the TLS requirement and instead transmit data unencrypted.(CVE-2026-4873)

libcurl might in some circumstances reuse the wrong connection when asked to do an authenticated HTTP(S) request after a Negotiate-authenticated one, when both use the same host.

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 credentials.

An application that first uses Negotiate authentication to a server with `user1:password1` and then does another operation to the same server asking for any authentication method but for `user2:password2` (while the previous connection is still alive) - the second request gets confused and wrongly reuses the same connection and sends the new request over that connection thinking it uses a mix of user1's and user2's creden…

curl-8.20.0-1.1 on GA media

curl: curl: Information disclosure due to incorrect TLS connection reuse curl: libcurl: Authentication bypass due to incorrect HTTP Negotiate connection reuse curl: libcurl: Wrong file transfer due to incorrect SMB connection reuse curl: curl: Proxy credential disclosure via redirects to unauthenticated proxies curl: libcurl: Information disclosure due to cookie leak when reusing connections with custom Host headers curl: libcurl: Credential leak via reused proxy connection during HTTP redirects

Security update for curl

Affected: Ubuntu:22.04:LTS: curl, Ubuntu:24.04:LTS: curl, Ubuntu:25.10: curl, Ubuntu:26.04:LTS: curl

Using libcurl, when a custom `Host:` header is first set for an HTTP request and a second request is subsequently done using the same *easy handle* but without the custom `Host:` header set, the second request would use stale information and pass on cookies meant for the first host in the second request. Leak them.

The vulnerabilities found in LabX Standard versions 21.3.22 - 21.4.23 are CVE-2025-69419, CVE-2026-0915, CVE-2025-15467, CVE-2026-4800, CVE-2026-33186, CVE-2026-39821, CVE-2026-33671 and are fixed in LabX Standard v21.4.25.

The vulnerabilities found in LabX Enterprise versions 21.3.22 - 21.4.23 are CVE-2026-4800, CVE-2026-33186, CVE-2026-39821, CVE-2026-33671 and are fixed in LabX Enterprise v21.4.25

All other vulnerabilities are to be fixed in the upcoming releases.

Ein Angreifer kann mehrere Schwachstellen in cURL ausnutzen, um Sicherheitsvorkehrungen zu umgehen, vertrauliche Informationen offenzulegen oder Daten zu manipulieren.