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USN-8790-1: Expat vulnerabilities

It was discovered that Expat could be made to allocate large amounts of memory when parsing a small crafted document. An attacker could possibly use this issue to cause Expat to consume resources, leading to a denial of service. This issue was only addressed in Ubuntu 24.04 LTS. (CVE-2025-59375) It was discovered that Expat incorrectly handled empty external parameter entity content. An attacker could possibly use this issue to cause Expat to crash, resulting in a denial of service. (CVE-2026-32776) It was discovered that Expat incorrectly handled certain DTD content. An attacker could possibly use this issue to cause Expat to enter an infinite loop, resulting in a denial of service. (CVE-2026-32777) It was discovered that Expat incorrectly handled memory when retrying after an earlier out-of-memory condition. An attacker could possibly use this issue to cause Expat to crash, resulting in a denial of service. (CVE-2026-32778) It was discovered that Expat performed attribute name collision checks inefficiently. An attacker could possibly use this issue to cause Expat to consume resources when processing a moderately sized crafted XML document, resulting in a denial of service. This issue was only addressed in Ubuntu 24.04 LTS and Ubuntu 26.04 LTS. (CVE-2026-45186) It was discovered that Expat used insufficient entropy, allowing hash flooding through a crafted XML document. An attacker could possibly use this issue to cause Expat to consume resources, leading to a denial of service. This issue was only addressed in Ubuntu 14.04 LTS, Ubuntu 24.04 LTS, and Ubuntu 26.04 LTS. (CVE-2026-41080) It was discovered that Expat did not track handler call depth for certain functions called from within handlers, leading to a use-after-free. An attacker could possibly use this issue to cause Expat to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2026-50219, CVE-2026-56412) It was discovered that Expat incorrectly handled certain values, leading to integer overflows. An attacker could possibly use this issue to cause Expat to crash, resulting in a denial of service. (CVE-2026-56403, CVE-2026-56404, CVE-2026-56405) It was discovered that Expat incorrectly handled certain values, leading to an integer overflow. An attacker could possibly use this issue to cause Expat to crash, resulting in a denial of service. This issue only affected Ubuntu 18.04 LTS, Ubuntu 20.04 LTS, Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, and Ubuntu 26.04 LTS. (CVE-2026-56408)

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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.