{ "document": { "aggregate_severity": { "text": "Medium" }, "category": "csaf_vex", "csaf_version": "2.0", "distribution": { "text": "TuxCare License Agreement", "tlp": { "label": "WHITE", "url": "https://www.first.org/tlp/" } }, "lang": "en", "notes": [ { "category": "legal_disclaimer", "text": "This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Cloud Linux Inc. and provide a link to the original.", "title": "Terms of Use" } ], "publisher": { "category": "vendor", "contact_details": "https://tuxcare.com/contact/", "name": "TuxCare", "namespace": "https://tuxcare.com/" }, "references": [ { "category": "self", "summary": "Canonical URL", "url": "https://security.tuxcare.com/csaf/v2/els_os/centos-stream8els/vex/2021/cve-2021-3448-els_os-centos-stream8els.json" } ], "tracking": { "current_release_date": "2026-06-12T14:26:34Z", "generator": { "date": "2026-06-12T14:26:34Z", "engine": { "name": "pyCSAF" } }, "id": "CVE-2021-3448-ELS_OS-CENTOS-STREAM8ELS", "initial_release_date": "2021-04-08T23:15:00Z", "revision_history": [ { "date": "2021-04-08T23:15:00Z", "number": "1", "summary": "Initial version" }, { "date": "2026-06-12T14:26:34Z", "number": "2", "summary": "Official Publication" } ], "status": "final", "version": "2" }, "title": "Security update on CVE-2021-3448" }, "product_tree": { "branches": [ { "branches": [ { "branches": [ { "category": "product_name", "name": "Community Enterprise Operating System 8", "product": { "name": "Community Enterprise Operating System 8", "product_id": "CentOS-Stream-8", "product_identification_helper": { "cpe": "cpe:2.3:o:centos:centos:8:*:*:*:*:*:*:*" } } } ], "category": "product_family", "name": "Community Enterprise Operating System" }, { "branches": [ { "category": "product_version", "name": "dnsmasq-utils-0:2.79-33.el8.x86_64", "product": { "name": "dnsmasq-utils-0:2.79-33.el8.x86_64", "product_id": "dnsmasq-utils-0:2.79-33.el8.x86_64", "product_identification_helper": { "purl": "pkg:rpm/centos/dnsmasq-utils@2.79-33.el8?arch=x86_64" } } }, { "category": "product_version", "name": "dnsmasq-0:2.79-33.el8.x86_64", "product": { "name": "dnsmasq-0:2.79-33.el8.x86_64", "product_id": "dnsmasq-0:2.79-33.el8.x86_64", "product_identification_helper": { "purl": "pkg:rpm/centos/dnsmasq@2.79-33.el8?arch=x86_64" } } } ], "category": "architecture", "name": "x86_64" } ], "category": "vendor", "name": "Red Hat, Inc." }, { "branches": [ { "branches": [ { "category": "product_version", "name": "dnsmasq-utils-0:2.79-33.el8.tuxcare.els1.x86_64", "product": { "name": "dnsmasq-utils-0:2.79-33.el8.tuxcare.els1.x86_64", "product_id": "dnsmasq-utils-0:2.79-33.el8.tuxcare.els1.x86_64", "product_identification_helper": { "purl": "pkg:rpm/tuxcare/dnsmasq-utils@2.79-33.el8.tuxcare.els1?arch=x86_64" } } }, { "category": "product_version", "name": "dnsmasq-0:2.79-33.el8.tuxcare.els1.x86_64", "product": { "name": "dnsmasq-0:2.79-33.el8.tuxcare.els1.x86_64", "product_id": "dnsmasq-0:2.79-33.el8.tuxcare.els1.x86_64", "product_identification_helper": { "purl": "pkg:rpm/tuxcare/dnsmasq@2.79-33.el8.tuxcare.els1?arch=x86_64" } } } ], "category": "architecture", "name": "x86_64" } ], "category": "vendor", "name": "TuxCare" } ], "relationships": [ { "category": "default_component_of", "full_product_name": { "name": "dnsmasq-utils-0:2.79-33.el8.tuxcare.els1.x86_64 as a component of Community Enterprise Operating System 8", "product_id": "CentOS-Stream-8:dnsmasq-utils-0:2.79-33.el8.tuxcare.els1.x86_64" }, "product_reference": "dnsmasq-utils-0:2.79-33.el8.tuxcare.els1.x86_64", "relates_to_product_reference": "CentOS-Stream-8" }, { "category": "default_component_of", "full_product_name": { "name": "dnsmasq-utils-0:2.79-33.el8.x86_64 as a component of Community Enterprise Operating System 8", "product_id": "CentOS-Stream-8:dnsmasq-utils-0:2.79-33.el8.x86_64" }, "product_reference": "dnsmasq-utils-0:2.79-33.el8.x86_64", "relates_to_product_reference": "CentOS-Stream-8" }, { "category": "default_component_of", "full_product_name": { "name": "dnsmasq-0:2.79-33.el8.tuxcare.els1.x86_64 as a component of Community Enterprise Operating System 8", "product_id": "CentOS-Stream-8:dnsmasq-0:2.79-33.el8.tuxcare.els1.x86_64" }, "product_reference": "dnsmasq-0:2.79-33.el8.tuxcare.els1.x86_64", "relates_to_product_reference": "CentOS-Stream-8" }, { "category": "default_component_of", "full_product_name": { "name": "dnsmasq-0:2.79-33.el8.x86_64 as a component of Community Enterprise Operating System 8", "product_id": "CentOS-Stream-8:dnsmasq-0:2.79-33.el8.x86_64" }, "product_reference": "dnsmasq-0:2.79-33.el8.x86_64", "relates_to_product_reference": "CentOS-Stream-8" } ] }, "vulnerabilities": [ { "cve": "CVE-2021-3448", "cwe": { "id": "CWE-358", "name": "Improperly Implemented Security Check for Standard" }, "notes": [ { "category": "description", "text": "A flaw was found in dnsmasq in versions before 2.85. When configured to use a specific server for a given network interface, dnsmasq uses a fixed port while forwarding queries. An attacker on the network, able to find the outgoing port used by dnsmasq, only needs to guess the random transmission ID to forge a reply and get it accepted by dnsmasq. This flaw makes a DNS Cache Poisoning attack much easier. The highest threat from this vulnerability is to data integrity.", "title": "Vulnerability description" }, { "category": "general", "text": "The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.", "title": "CVSS score applicability" } ], "product_status": { "known_affected": [ "CentOS-Stream-8:dnsmasq-0:2.79-33.el8.tuxcare.els1.x86_64", "CentOS-Stream-8:dnsmasq-0:2.79-33.el8.x86_64", "CentOS-Stream-8:dnsmasq-utils-0:2.79-33.el8.tuxcare.els1.x86_64", "CentOS-Stream-8:dnsmasq-utils-0:2.79-33.el8.x86_64" ] }, "references": [ { "category": "self", "summary": "Canonical URL", "url": "https://cve.tuxcare.com/els/cve/CVE-2021-3448" }, { "category": "external", "summary": "https://bugzilla.redhat.com/show_bug.cgi?id=1939368", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=1939368" }, { "category": "external", "summary": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CVTJUOFFFHINLKWAOC2ZSC5MOPD4SJ24/", "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CVTJUOFFFHINLKWAOC2ZSC5MOPD4SJ24/" }, { "category": "external", "summary": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FHG7GWSQWKF7JXIMLOGJBKZWBB4VIAJ7/", "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FHG7GWSQWKF7JXIMLOGJBKZWBB4VIAJ7/" }, { "category": "external", "summary": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GHURNEHHUBSW45KMIZ4FNBCSUPWPGV5V/", "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GHURNEHHUBSW45KMIZ4FNBCSUPWPGV5V/" }, { "category": "external", "summary": "https://security.gentoo.org/glsa/202105-20", "url": "https://security.gentoo.org/glsa/202105-20" }, { "category": "external", "summary": "https://www.oracle.com/security-alerts/cpujan2022.html", "url": "https://www.oracle.com/security-alerts/cpujan2022.html" } ], "release_date": "2021-04-08T23:15:00Z", "remediations": [ { "category": "no_fix_planned", "date": "2026-06-12T13:07:14.589380Z", "details": "This flaw only applies when dnsmasq is configured with the non-default “--server … @” option that pins an upstream server to a specific interface; standard configurations that do not use interface-qualified servers are not affected. Even then, an attacker must be on the local network path and win a high‑complexity race by guessing the 16‑bit DNS transaction ID after learning the fixed source port, with no confidentiality or availability impact and only limited integrity impact on cached entries. Given these configuration-specific prerequisites and the on‑path requirement, this is a low‑priority issue for typical enterprise servers and cloud VMs.", "product_ids": [ "CentOS-Stream-8:dnsmasq-0:2.79-33.el8.tuxcare.els1.x86_64", "CentOS-Stream-8:dnsmasq-0:2.79-33.el8.x86_64", "CentOS-Stream-8:dnsmasq-utils-0:2.79-33.el8.tuxcare.els1.x86_64", "CentOS-Stream-8:dnsmasq-utils-0:2.79-33.el8.x86_64" ] } ], "scores": [ { "cvss_v2": { "accessComplexity": "MEDIUM", "accessVector": "NETWORK", "authentication": "NONE", "availabilityImpact": "NONE", "baseScore": 4.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "PARTIAL", "vectorString": "AV:N/AC:M/Au:N/C:N/I:P/A:N", "version": "2.0" }, "cvss_v3": { "attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 4.0, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "LOW", "privilegesRequired": "NONE", "scope": "CHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N", "version": "3.1" }, "products": [ "CentOS-Stream-8:dnsmasq-0:2.79-33.el8.tuxcare.els1.x86_64", "CentOS-Stream-8:dnsmasq-0:2.79-33.el8.x86_64", "CentOS-Stream-8:dnsmasq-utils-0:2.79-33.el8.tuxcare.els1.x86_64", "CentOS-Stream-8:dnsmasq-utils-0:2.79-33.el8.x86_64" ] } ], "threats": [ { "category": "impact", "details": "Moderate" } ] } ] }