CVE-2026-116566

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{"bugzilla": {"description": "python: python: Security bypass via null byte truncation in socket.getaddrinfo()", "id": "2563615", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2563615"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.3", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N", "status": "draft"}, "cwe": "CWE-140", "details": ["socket.getaddrinfo() previously accepted null bytes within *host* and *port* parameters which can cause the values to be silently truncated.", "A flaw was found in Python. An attacker could bypass security controls and redirect network connections to unintended destinations due to improper input handling in the socket.getaddrinfo() function. Specifically, when host or port parameters contain null byte characters, the values are silently truncated during address resolution. This flaw enables attackers who supply network inputs to evade validation filters, such as domain or port allowlists."], "mitigation": {"lang": "en:us", "value": "Reject or sanitize null bytes in host and port values before calling socket.getaddrinfo(), or upgrade to CPython 3.16.0+ or a build carrying the backported fix (upstream PRs #160925/#160926/#160974/#160975/#160977 for 3.15/3.14/3.13/3.12/3.11)."}, "name": "CVE-2026-116566", "package_state": [{"cpe": "cpe:/a:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "python3.12", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/a:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "python3.14", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:rhel_els:6", "fix_state": "Out of support scope", "package_name": "python", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:rhel_els:7", "fix_state": "Fix deferred", "package_name": "python", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:rhel_els:7", "fix_state": "Fix deferred", "package_name": "python3", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/a:redhat:enterprise_linux:8", "fix_state": "Fix deferred", "package_name": "python3", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/a:redhat:enterprise_linux:8", "fix_state": "Fix deferred", "package_name": "python3.12", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/a:redhat:enterprise_linux:8", "fix_state": "Fix deferred", "package_name": "python36:3.6/python36", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/a:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "python3.12", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "python3.14", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "python3.9", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:enterprise_linux_ai:3", "fix_state": "Fix deferred", "package_name": "rhelai3/bootc-aws-cuda-rhel9", "product_name": "Red Hat Enterprise Linux AI (RHEL AI) 3"}, {"cpe": "cpe:/a:redhat:enterprise_linux_ai:3", "fix_state": "Fix deferred", "package_name": "rhelai3/bootc-azure-cuda-rhel9", "product_name": "Red Hat Enterprise Linux AI (RHEL AI) 3"}, {"cpe": "cpe:/a:redhat:enterprise_linux_ai:3", "fix_state": "Fix deferred", "package_name": "rhelai3/bootc-azure-rocm-rhel9", "product_name": "Red Hat Enterprise Linux AI (RHEL AI) 3"}, {"cpe": "cpe:/a:redhat:enterprise_linux_ai:3", "fix_state": "Fix deferred", "package_name": "rhelai3/bootc-cuda-rhel9", "product_name": "Red Hat Enterprise Linux AI (RHEL AI) 3"}, {"cpe": "cpe:/a:redhat:enterprise_linux_ai:3", "fix_state": "Fix deferred", "package_name": "rhelai3/bootc-gaudi-rhel9", "product_name": "Red Hat Enterprise Linux AI (RHEL AI) 3"}, {"cpe": "cpe:/a:redhat:enterprise_linux_ai:3", "fix_state": "Fix deferred", "package_name": "rhelai3/bootc-gcp-cuda-rhel9", "product_name": "Red Hat Enterprise Linux AI (RHEL AI) 3"}, {"cpe": "cpe:/a:redhat:enterprise_linux_ai:3", "fix_state": "Fix deferred", "package_name": "rhelai3/bootc-rocm-rhel9", "product_name": "Red Hat Enterprise Linux AI (RHEL AI) 3"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Will not fix", "package_name": "python3.10", "product_name": "Red Hat Hardened Images"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "package_name": "python3.11", "product_name": "Red Hat Hardened Images"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "package_name": "python3.12", "product_name": "Red Hat Hardened Images"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "package_name": "python3.13", "product_name": "Red Hat Hardened Images"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "package_name": "python3.14", "product_name": "Red Hat Hardened Images"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "package_name": "python3.15", "product_name": "Red Hat Hardened Images"}, {"cpe": "cpe:/a:redhat:container_native_virtualization:4", "fix_state": "Fix deferred", "package_name": "container-native-virtualization/ocp-virt-validation-checkup-rhel9", "product_name": "Red Hat OpenShift Virtualization 4"}, {"cpe": "cpe:/a:redhat:ansible_portal:2", "fix_state": "Fix deferred", "package_name": "ansible-automation-platform/bootc-automation-portal-rhel9", "product_name": "Self-service automation portal 2"}], "public_date": "2026-10-29T17:45:47Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-116566\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-116566\nhttps://github.com/python/cpython/issues/160898\nhttps://github.com/python/cpython/pull/160899\nhttps://mail.python.org/archives/list/security-announce@python.org/thread/HCHE62VYTPYI6WOPJQDWUBR4CINBPSM7/"], "statement": "Red Hat has evaluated this vulnerability as Moderate because exploitation is limited to applications that forward unsanitized external input to hostname resolution routines while relying on prefix-based or suffix-based validation. While an attacker can cause target destinations to be interpreted differently by the resolver compared to preceding security checks, this does not directly compromise system integrity or allow arbitrary remote code execution. Standard system utilities and hardened network services that perform strict input verification or resolve predefined endpoints remain unaffected.", "threat_severity": "Moderate"}

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