CVE-2026-107708

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By sending an S4U2Proxy delegation request containing a malformed client name within a Privilege Attribute Certificate (PAC), an attacker can trigger a NULL pointer dereference that crashes the KDC daemon, interrupting authentication services."], "name": "CVE-2026-107708", "package_state": [{"cpe": "cpe:/a:redhat:migration_toolkit_virtualization:2", "fix_state": "Fix deferred", "package_name": "migration-toolkit-virtualization/mtv-virt-v2v-rhel10", "product_name": "Migration Toolkit for Virtualization"}, {"cpe": "cpe:/a:redhat:certifications:9", "fix_state": "Fix deferred", "package_name": "rhcertification/redhat-certification-baremetal", "product_name": "Red Hat Certification Program for Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:certifications:9", "fix_state": "Fix deferred", "package_name": "rhcertification/redhat-certification-system-ai-10", "product_name": "Red Hat Certification Program for Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:certifications:9", "fix_state": "Fix deferred", "package_name": "rhcertification/redhat-certification-system-ai-9", "product_name": "Red Hat Certification Program for Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "krb5", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "rhel10-eus/rhel-10.0-bootc", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "rhel10-eus/rhel-10.2-bootc", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "rhel10/rhel-bootc", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Out of support scope", "package_name": "krb5", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Fix deferred", "package_name": "krb5", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Fix deferred", "package_name": "krb5", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "krb5", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "rhel9-eus/rhel-9.6-bootc", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "rhel9-eus/rhel-9.8-bootc", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "rhel9/rhel-bootc", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "package_name": "krb5", "product_name": "Red Hat Hardened Images"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Fix deferred", "package_name": "openshift4/driver-toolkit-rhel9", "product_name": "Red Hat OpenShift Container Platform 4"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Fix deferred", "package_name": "openshift4/ose-ironic-machine-os-downloader-rhel9", "product_name": "Red Hat OpenShift Container Platform 4"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Fix deferred", "package_name": "openshift/ose-rhel-coreos-8", "product_name": "Red Hat OpenShift Container Platform 4"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Fix deferred", "package_name": "openshift/ose-rhel-coreos-9", "product_name": "Red Hat OpenShift Container Platform 4"}, {"cpe": "cpe:/a:redhat:openstack:18.0", "fix_state": "Fix deferred", "package_name": "rhoso/openstack-nova-compute-rhel9", "product_name": "Red Hat OpenStack Platform 18.0"}], "public_date": "2026-10-08T20:15:53Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-107708\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-107708\nhttps://github.com/krb5/krb5\nhttps://github.com/krb5/krb5/blob/krb5-1.22.2-final/src/kdc/kdc_util.c#L639-L676\nhttps://github.com/krb5/krb5/commit/a88a18cafa1040a0c4f9c8d08288fc98831ec86d\nhttps://github.com/krb5/krb5/commit/f6e2c397ceda6467ebbaab8ed66d4895c9f1d6a7\nhttps://github.com/krb5/krb5/pull/1510\nhttps://www.vulncheck.com/advisories/mit-krb5-through-1.22.2-kdc-null-pointer-dereference-via-s4u2proxy-pac"], "threat_severity": "Moderate"}

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