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USN-8365-1: Dovecot vulnerabilities

It was discovered that Dovecot incorrectly treated some variable expansion pipelines as safe in authentication filters. An attacker could possibly use this issue to perform SQL or LDAP injection attacks. This issue only affected Ubuntu 25.10 and Ubuntu 26.04 LTS. (CVE-2026-27851) It was discovered that Dovecot incorrectly verified SCRAM TLS channel binding in certain base64 exchanges. A remote attacker could possibly use this issue to obtain sensitive information in a machine-in-the-middle attack. (CVE-2026-33603) It was discovered that Dovecot incorrectly enforced Sieve script CPU limits. An attacker could possibly use this issue to cause Dovecot to use excessive resources, leading to a denial of service. (CVE-2026-40016) It was discovered that Dovecot incorrectly handled certain IMAP SETACL commands. An attacker could possibly use this issue to spam folders to other users. (CVE-2026-40020) It was discovered that Dovecot incorrectly handled excessive IMAP bracing. An attacker could possibly use this issue to cause Dovecot to use excessive resources, leading to a denial of service. (CVE-2026-42006)

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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.