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USN-8487-1: curl vulnerabilities

Andrew Nesbitt discovered that curl could reuse an existing live connection during STARTTLS-based connection upgrades even when the TLS configuration did not match. A remote attacker could possibly use this issue to cause curl to use an unintended TLS configuration. (CVE-2026-8286) Muhamad Arga Reksapati discovered that curl incorrectly reused connections for Negotiate-authenticated requests when different services were involved. A remote attacker could possibly use this issue to access resources authenticated for another service. This issue only affected Ubuntu 18.04 LTS, Ubuntu 20.04 LTS, Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, Ubuntu 25.10, and Ubuntu 26.04 LTS. (CVE-2026-8458) It was discovered that curl incorrectly handled cookie parsing in certain circumstances. A remote attacker could possibly use this issue to set cookies that would be transmitted to unrelated third-party domains. This issue only affected Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, Ubuntu 20.04 LTS, Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, Ubuntu 25.10, and Ubuntu 26.04 LTS. (CVE-2026-8924) Joshua Rogers discovered that curl could double-free a GSASL context when handling SASL authentication. A remote attacker could possibly use this issue to cause a denial of service, or execute arbitrary code. This issue only affected Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, Ubuntu 25.10, and Ubuntu 26.04 LTS. (CVE-2026-8925) Joshua Rogers discovered that curl could select the wrong password from a .netrc file when a username was specified in the URL without a password. A remote attacker could possibly use this issue to obtain sensitive information. This issue only affected Ubuntu 25.10 and Ubuntu 26.04 LTS. (CVE-2026-8926) Ady Elouej discovered that curl did not clear proxy authentication state between requests when reusing a handle with environment-variable proxy configuration. A remote attacker could possibly use this issue to obtain sensitive credentials. (CVE-2026-8927) Guannan Wang, Zhanpeng Liu, Jiashuo Liang, and Guancheng Li discovered that curl did not properly clear proxy authentication credentials when instructed to do so. A remote attacker could possibly use this issue to obtain sensitive credentials. This issue only affected Ubuntu 25.10 and Ubuntu 26.04 LTS. (CVE-2026-9079) Joshua Rogers discovered that curl contained a use-after-free when curl_easy_pause() was called within the event-based socket callback. A remote attacker could possibly use this issue to cause a denial of service or possibly execute arbitrary code. This issue only affected Ubuntu 25.10 and Ubuntu 26.04 LTS. (CVE-2026-9080) Eunsoo Kim discovered that curl could send early data on a resumed TLS session before enforcing certificate verification failure. A machine-in-the-middle attacker could possibly use this issue to obtain sensitive information. This issue only affected Ubuntu 25.10 and Ubuntu 26.04 LTS. (CVE-2026-9545) Joshua Rogers discovered that curl did not properly reject host key type mismatches when using the SSH key callback for SCP and SFTP transfers. A machine-in-the-middle attacker could possibly use this issue to impersonate a trusted server. This issue only affected Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, Ubuntu 25.10, and Ubuntu 26.04 LTS. (CVE-2026-9547)

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Kenya Education Network CERT(KENET-CERT) is a Cybersecurity Emergency Response Team and Co-ordination Center operated by the National Research and Education Network of Kenya. KENET-CERT coordination center promotes awareness on cybersecurity incidences as well as coordinates and assists member institutions in responding effectively to cyber security threats and incidences. KENET-CERT works closely with Kenya's National CIRT coordination center (CIRT/CC) as a sector CIRT for the academic institutions. KENET promotes use of ICT in Teaching, Learning and Research in Higher Education Institutions in Kenya. KENET aims to interconnect all the Universities, Tertiary and Research Institutions in Kenya by setting up a cost effective and sustainable private network with high speed access to the global Internet. KENET also facilitates electronic communication among students and faculties in member institutions, share learning and teaching resources by collaboration in Research and Development of Educational content.