[USN-8227-1] curl vulnerabilities

========================================================================== Ubuntu Security Notice USN-8227-1 May 04, 2026 curl vulnerabilities ========================================================================== A security issue affects these releases of Ubuntu and its derivatives: - Ubuntu 26.04 LTS - Ubuntu 25.10 - Ubuntu 24.04 LTS - Ubuntu 22.04 LTS Summary: curl could be made to expose sensitive information over the network. Software Description: - curl: HTTP, HTTPS, and FTP client and client libraries Details: It was discovered that curl incorrectly reused non-TLS connections when TLS was required in some STARTTLS configurations. A remote attacker could possibly use this issue to obtain sensitive information. (CVE-2026-4873) It was discovered that curl incorrectly reused certain HTTP Negotiate connections. A remote attacker could possibly use this issue to obtain sensitive information. (CVE-2026-5545) It was discovered that curl incorrectly reused certain SMB connections. A remote attacker could possibly use this issue to obtain sensitive information. (CVE-2026-5773) It was discovered that curl could leak proxy credentials when handling redirects in some configurations. A remote attacker could possibly use this issue to obtain sensitive information. (CVE-2026-6253) It was discovered that curl could leak cookies because of stale custom cookie host handling in some requests. A remote attacker could possibly use this issue to obtain sensitive information. (CVE-2026-6276) It was discovered that curl could leak .netrc credentials when reusing proxy connections in some situations. A remote attacker could possibly use this issue to obtain sensitive information. (CVE-2026-6429) It was discovered that curl could leak Digest authentication state when switching proxies in some situations. A remote attacker could possibly use this issue to obtain sensitive information. (CVE-2026-7168) Update instructions: The problem can be corrected by updating your system to the following package versions: Ubuntu 26.04 LTS curl 8.18.0-1ubuntu2.1 libcurl3t64-gnutls 8.18.0-1ubuntu2.1 libcurl4t64 8.18.0-1ubuntu2.1 Ubuntu 25.10 curl 8.14.1-2ubuntu1.3 libcurl3t64-gnutls 8.14.1-2ubuntu1.3 libcurl4t64 8.14.1-2ubuntu1.3 Ubuntu 24.04 LTS curl 8.5.0-2ubuntu10.9 libcurl3t64-gnutls 8.5.0-2ubuntu10.9 libcurl4t64 8.5.0-2ubuntu10.9 Ubuntu 22.04 LTS curl 7.81.0-1ubuntu1.24 libcurl3-gnutls 7.81.0-1ubuntu1.24 libcurl3-nss 7.81.0-1ubuntu1.24 libcurl4 7.81.0-1ubuntu1.24 In general, a standard system update will make all the necessary changes. References: https://ubuntu.com/security/notices/USN-8227-1 CVE-2026-4873, CVE-2026-5545, CVE-2026-5773, CVE-2026-6253, CVE-2026-6276, CVE-2026-6429, CVE-2026-7168 Package Information: https://launchpad.net/ubuntu/+source/curl/8.18.0-1ubuntu2.1 https://launchpad.net/ubuntu/+source/curl/8.14.1-2ubuntu1.3 https://launchpad.net/ubuntu/+source/curl/8.5.0-2ubuntu10.9 https://launchpad.net/ubuntu/+source/curl/7.81.0-1ubuntu1.24