CVE-2026-84378

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{"bugzilla": {"description": "httpx2: HTTPX2: Denial of Service via crafted Server-Sent Events stream", "id": "2527694", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2527694"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.9", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-606", "details": ["A flaw was found in httpx2, a Python HTTP client. The Server-Sent Events (SSE) parser in httpx2 can be exploited by a remote attacker. By sending a specially crafted stream where an unterminated line is split across many response chunks, the parser repeatedly copies and rescans buffered text. This quadratic processing work consumes excessive CPU resources, leading to a Denial of Service (DoS) by blocking synchronous workers or asynchronous event loops."], "name": "CVE-2026-84378", "package_state": [{"cpe": "cpe:/a:redhat:lightspeed_core", "fix_state": "Fix deferred", "package_name": "lightspeed-core/lightspeed-stack-rhel9", "product_name": "Lightspeed Core"}, {"cpe": "cpe:/a:redhat:openshift_ai", "fix_state": "Fix deferred", "package_name": "rhoai/odh-automl-rhel9", "product_name": "Red Hat OpenShift AI (RHOAI)"}, {"cpe": "cpe:/a:redhat:openshift_ai", "fix_state": "Fix deferred", "package_name": "rhoai/odh-kserve-autogluon-server-rhel9", "product_name": "Red Hat OpenShift AI (RHOAI)"}, {"cpe": "cpe:/a:redhat:openshift_ai", "fix_state": "Fix deferred", "package_name": "rhoai/odh-kserve-storage-initializer-rhel9", "product_name": "Red Hat OpenShift AI (RHOAI)"}], "public_date": "2026-09-02T17:54:19Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-84378\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-84378\nhttps://github.com/pydantic/httpx2/commit/cbfc0e04ef6507da29ccbb3b9c2e5b23dd693414\nhttps://github.com/pydantic/httpx2/pull/1071\nhttps://github.com/pydantic/httpx2/pull/1117\nhttps://github.com/pydantic/httpx2/releases/tag/v2.10.0\nhttps://github.com/pydantic/httpx2/security/advisories/GHSA-f2fp-rgf2-35cp"], "threat_severity": "Moderate"}

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