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{"bugzilla": {"description": "io.netty/netty-codec-http3: netty-codec-http3: Denial of Service via unbounded QPACK encoder memory retention", "id": "2541808", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2541808"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.5", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-770", "details": ["A flaw was found in Netty's HTTP/3 codec (netty-codec-http3). The HTTP/3 header compression (QPACK) encoder stores per-stream state indefinitely when remote clients do not acknowledge encoded data, as no memory limits are enforced. A remote, unauthenticated attacker can exploit this flaw by issuing sequential requests over a single connection while withholding stream acknowledgment instructions. This causes unbounded memory consumption on the server, ultimately resulting in memory exhaustion and a Denial of Service (DoS)."], "name": "CVE-2026-100660", "package_state": [{"cpe": "cpe:/a:redhat:openshift_ai", "fix_state": "Affected", "package_name": "rhoai/odh-th-torch-cpu-py312-rhel9", "product_name": "Red Hat OpenShift AI (RHOAI)"}, {"cpe": "cpe:/a:redhat:openshift_ai", "fix_state": "Affected", "package_name": "rhoai/odh-th-torch-cuda-py312-rhel9", "product_name": "Red Hat OpenShift AI (RHOAI)"}, {"cpe": "cpe:/a:redhat:openshift_devspaces:3", "fix_state": "Affected", "package_name": "devspaces/openvsx-rhel9", "product_name": "Red Hat OpenShift Dev Spaces"}, {"cpe": "cpe:/a:redhat:openshift_devspaces:3", "fix_state": "Affected", "package_name": "devspaces/pluginregistry-rhel9", "product_name": "Red Hat OpenShift Dev Spaces"}], "public_date": "2026-09-26T13:23:27Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-100660\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-100660\nhttps://github.com/netty/netty/security/advisories/GHSA-495p-pchh-r4mc\nhttps://www.vulncheck.com/advisories/netty-before-4.2.18-final-qpackencoder-unbounded-memory-retention"], "threat_severity": "Important"}

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