curl: Use-After-Free race condition in url_move_hostname() via shared connection pool

Summary: In lib/url.c, urlconnreuseadjust calls urlmovehostname which frees conn-host.rawalloc and conn-host.encalloc via Curlsafefree and Curlfreeidnconvertedhostname after Curlcpoolfind has already released the connection pool lock. A second thread doing a concurrent pool lookup still holds tha...

curl: HackerOne Vulnerability Report: libcurl SSL/TLS Identity Leakage via Insecure Connection Reuse

Summary libcurl contains a critical logic flaw in its connection reuse mechanism where transfers using the CURLOPTSSLCTXFUNCTION SSL context callback to establish a specific identity e.g., via client certificates can have their connections incorrectly reused by subsequent, unauthenticated transfe...

curl: Unbounded GZIP Decompression Leading to Event-Loop Starvation

When libcurl is configured to decompress HTTP responses via CURLOPTACCEPTENCODING or the --compressed CLI flag, it lacks decompression bounds checking or a mechanism to yield execution during massive expansion tasks. If an attacker provides a highly compressed payload zip bomb, libcurl's underlyi...

The vulnerability of the libcurl library in software applications for interacting with servers via cURL allows attackers to compromise the confidentiality of protected information.

The vulnerability of the libcurl library in software applications for interacting with servers via cURL is related to improper verification of certificate authenticity. Exploiting this vulnerability allows an attacker to compromise the confidentiality of the protected information...

Curl 7.10.6 < 8.19.0 Authentication Bypass

The version of curl installed on the remote host is 7.10.6 prior to 8.19.0. It is, therefore, affected by an authentication bypass vulnerability: - libcurl can in some circumstances reuse the wrong connection when asked to do an Negotiate-authenticated HTTP or HTTPS request. libcurl features a po...

CVE-2026-1965

libcurl can in some circumstances reuse the wrong connection when asked to do an Negotiate-authenticated HTTP or HTTPS request. 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...

UBUNTU-CVE-2026-1965

libcurl can in some circumstances reuse the wrong connection when asked to do an Negotiate-authenticated HTTP or HTTPS request. 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...

SUSE CVE-2026-1965

libcurl can in some circumstances reuse the wrong connection when asked to do an Negotiate-authenticated HTTP or HTTPS request. 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...

EUVD-2026-11135

libcurl can in some circumstances reuse the wrong connection when asked to do an Negotiate-authenticated HTTP or HTTPS request. 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...

CVE-2026-1965 bad reuse of HTTP Negotiate connection

libcurl can in some circumstances reuse the wrong connection when asked to do an Negotiate-authenticated HTTP or HTTPS request. 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...

CVE-2026-1965 bad reuse of HTTP Negotiate connection

libcurl can in some circumstances reuse the wrong connection when asked to do an Negotiate-authenticated HTTP or HTTPS request. 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...

CVE-2026-1965

libcurl can in some circumstances reuse the wrong connection when asked to do an Negotiate-authenticated HTTP or HTTPS request. 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...

CVE-2026-1965 bad reuse of HTTP Negotiate connection

libcurl can in some circumstances reuse the wrong connection when asked to do an Negotiate-authenticated HTTP or HTTPS request. 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...

CVE-2026-1965

libcurl can in some circumstances reuse the wrong connection when asked to do an Negotiate-authenticated HTTP or HTTPS request. 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...

CVE-2026-1965

libcurl can in some circumstances reuse the wrong connection when asked to do an Negotiate-authenticated HTTP or HTTPS request. 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...

CURL-CVE-2026-1965 bad reuse of HTTP Negotiate connection

libcurl can in some circumstances reuse the wrong connection when asked to do an Negotiate-authenticated HTTP or HTTPS request. 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...

curl: NULL Pointer Dereference (DoS) in libcurl SFTP QUOTE command parsing due to missing return statement

Summary: A logic flaw in lib/vssh/libssh2.c causes a NULL pointer dereference when parsing SFTP QUOTE commands with trailing garbage. The function returnquoteerror is called to handle errors and free memory, but the return keyword is missing in several blocks e.g., lines 840, 857, 870. This allow...

Linux Distros Unpatched Vulnerability : CVE-2026-1965

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available. - libcurl can in some circumstances reuse the wrong connection when asked to do an Negotiate-authenticated HTTP or HTTPS request. libcurl features a pool of recen...

Amazon Linux 2023 : curl, curl-minimal, libcurl (ALAS2023-2026-1375)

It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2023-2026-1375 advisory. No QUIC certificate pinning with GnuTLS NOTE: https://curl.se/docs/CVE-2025-13034.htmlNOTE: Introduced with: https://github.com/curl/curl/commit/3210101088dfa3d6a125d213226b092f2f866722...

[R2] Stand-alone Security Patches Available for Tenable Security Center versions 6.5.1, 6.6.0 and 6.7.2: SC-202602.1 + SC-202602.2

R2 Stand-alone Security Patches Available for Tenable Security Center versions 6.5.1, 6.6.0 and 6.7.2: SC-202602.1 + SC-202602.2 Arnie Cabral Tue, 02/17/2026 - 08:32 Security Center leverages third-party software to help provide underlying functionality. Several of the third-party components...