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USN-8932-1: curl vulnerabilities

Stanislav Fort discovered that curl did not properly clear AWS SigV4 authentication state when CURLOPT_AWS_SIGV4 was set to NULL. An attacker could possibly use this issue to obtain sensitive information. This issue only affected Ubuntu 22.04 LTS and Ubuntu 24.04 LTS. (CVE-2026-86409) Stanislav Fort discovered that an HTTP proxy could trick libcurl into sending credentials to the proxy itself by responding to a CONNECT request with an unexpected authentication challenge. An attacker could possibly use this issue to obtain sensitive information. (CVE-2026-86414) Stanislav Fort discovered that curl did not correctly handle HSTS entries when an includeSubDomains parent entry was imported before a longer-lived child entry. An attacker could possibly use this issue to cause curl to use unencrypted HTTP connections. This issue only affected Ubuntu 22.04 LTS and Ubuntu 24.04 LTS. (CVE-2026-87862) Stanislav Fort discovered that curl did not properly handle HSTS max-age values that exceeded calendar time structure bounds. An attacker could possibly use this issue to cause a denial of service or data loss. This issue only affected Ubuntu 24.04 LTS. (CVE-2026-87863) Stanislav Fort discovered that curl did not properly handle IMAP APPEND commands when CURLOPT_CRLF was enabled, allowing overflow bytes to be interpreted as pipelined commands. An authenticated attacker could possibly use this issue to inject arbitrary IMAP commands. (CVE-2026-87864) Joshua Rogers discovered that libcurl had a use-after-free vulnerability in the FTP wildcard matching code. An attacker could possibly use this issue to cause curl to crash, resulting in a denial of service, or execute arbitrary code. (CVE-2026-92388) Joshua Rogers discovered that libcurl's TFTP state machine did not properly validate transfer directions, allowing a malicious server to force the client into transmit mode. An attacker could possibly use this issue to obtain sensitive information. (CVE-2026-92389) Joshua Rogers discovered that curl had a stack overflow vulnerability when processing deeply nested MIME structures. An attacker could possibly use this issue to cause curl to crash, resulting in a denial of service. This issue only affected Ubuntu 18.04 LTS, Ubuntu 20.04 LTS, Ubuntu 22.04 LTS and Ubuntu 24.04 LTS. (CVE-2026-92391) Joshua Rogers discovered that libcurl could expose credentials in the URL returned by CURLINFO_EFFECTIVE_URL when credentials were retrieved from a .netrc file. An attacker could possibly use this issue to obtain sensitive information. This issue only affected Ubuntu 20.04 LTS, Ubuntu 22.04 LTS and Ubuntu 24.04 LTS. (CVE-2026-94266)

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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.