CVE-2020-25682

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{}

{"affected": [{"affectedData": [{"product": "dnsmasq", "vendor": "n/a", "versions": [{"status": "affected", "version": "dnsmasq 2.83"}]}], "source": "secalert@redhat.com"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:thekelleys:dnsmasq:*:*:*:*:*:*:*:*", "matchCriteriaId": "F38115DF-0F5C-442D-83D4-1125AAB4E2B7", "versionEndExcluding": "2.83", "vulnerable": true}], "negate": false, "operator": "OR"}]}, {"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*", "matchCriteriaId": "36D96259-24BD-44E2-96D9-78CE1D41F956", "vulnerable": true}, {"criteria": "cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*", "matchCriteriaId": "E460AA51-FCDA-46B9-AE97-E6676AA5E194", "vulnerable": true}], "negate": false, "operator": "OR"}]}, {"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*", "matchCriteriaId": "DEECE5FC-CACF-4496-A3E7-164736409252", "vulnerable": true}, {"criteria": "cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*", "matchCriteriaId": "07B237A9-69A3-4A9C-9DA0-4E06BD37AE73", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "A flaw was found in dnsmasq before 2.83. A buffer overflow vulnerability was discovered in the way dnsmasq extract names from DNS packets before validating them with DNSSEC data. An attacker on the network, who can create valid DNS replies, could use this flaw to cause an overflow with arbitrary data in a heap-allocated memory, possibly executing code on the machine. The flaw is in the rfc1035.c:extract_name() function, which writes data to the memory pointed by name assuming MAXDNAME*2 bytes are available in the buffer. However, in some code execution paths, it is possible extract_name() gets passed an offset from the base buffer, thus reducing, in practice, the number of available bytes that can be written in the buffer. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability."}, {"lang": "es", "value": "Se encontr\u00f3 un fallo en dnsmasq versiones anteriores a 2.83. Se detect\u00f3 una vulnerabilidad de desbordamiento del b\u00fafer en la manera en que dnsmasq extrae nombres de paquetes DNS antes de validarlos con datos DNSSEC. Un atacante en la red, que puede crear respuestas DNS v\u00e1lidas, podr\u00eda usar este fallo para causar un desbordamiento de datos arbitrarios en una memoria asignada de la pila, posiblemente ejecutando c\u00f3digo en la m\u00e1quina. El fallo est\u00e1 en la funci\u00f3n rfc1035.c:extract_name(), que escribe datos en la memoria apuntada por el nombre asumiendo que los bytes MAXDNAME*2 est\u00e1n disponibles en el b\u00fafer. Sin embargo, en algunas rutas de ejecuci\u00f3n de c\u00f3digo, es posible que la funci\u00f3n extract_name() pasaba un desplazamiento del b\u00fafer base, reduciendo as\u00ed, en la pr\u00e1ctica, el n\u00famero de bytes disponibles que se pueden escribir en el b\u00fafer. La mayor amenaza de esta vulnerabilidad es la confidencialidad e integridad de los datos, as\u00ed como la disponibilidad del sistema"}], "id": "CVE-2020-25682", "lastModified": "2026-06-17T03:07:07.160", "metrics": {"cvssMetricV2": [{"acInsufInfo": false, "baseSeverity": "HIGH", "cvssData": {"accessComplexity": "MEDIUM", "accessVector": "NETWORK", "authentication": "NONE", "availabilityImpact": "COMPLETE", "baseScore": 8.3, "confidentialityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "vectorString": "AV:N/AC:M/Au:N/C:P/I:P/A:C", "version": "2.0"}, "exploitabilityScore": 8.6, "impactScore": 8.5, "obtainAllPrivilege": false, "obtainOtherPrivilege": false, "obtainUserPrivilege": false, "source": "nvd@nist.gov", "type": "Primary", "userInteractionRequired": false}], "cvssMetricV31": [{"cvssData": {"attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 8.1, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 2.2, "impactScore": 5.9, "source": "nvd@nist.gov", "type": "Primary"}]}, "published": "2021-01-20T17:15:12.920", "references": [{"source": "secalert@redhat.com", "tags": ["Issue Tracking", "Patch", "Third Party Advisory"], "url": "https://bugzilla.redhat.com/show_bug.cgi?id=1882014"}, {"source": "secalert@redhat.com", "tags": ["Mailing List", "Third Party Advisory"], "url": "https://lists.debian.org/debian-lts-announce/2021/03/msg00027.html"}, {"source": "secalert@redhat.com", "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QGB7HL3OWHTLEPSMLDGOMXQKG3KM2QME/"}, {"source": "secalert@redhat.com", "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WYW3IR6APUSKOYKL5FT3ACTIHWHGQY32/"}, {"source": "secalert@redhat.com", "tags": ["Third Party Advisory"], "url": "https://security.gentoo.org/glsa/202101-17"}, {"source": "secalert@redhat.com", "tags": ["Third Party Advisory"], "url": "https://www.debian.org/security/2021/dsa-4844"}, {"source": "secalert@redhat.com", "tags": ["Third Party Advisory"], "url": "https://www.jsof-tech.com/disclosures/dnspooq/"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Issue Tracking", "Patch", "Third Party Advisory"], "url": "https://bugzilla.redhat.com/show_bug.cgi?id=1882014"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Mailing List", "Third Party Advisory"], "url": "https://lists.debian.org/debian-lts-announce/2021/03/msg00027.html"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QGB7HL3OWHTLEPSMLDGOMXQKG3KM2QME/"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WYW3IR6APUSKOYKL5FT3ACTIHWHGQY32/"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Third Party Advisory"], "url": "https://security.gentoo.org/glsa/202101-17"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Third Party Advisory"], "url": "https://www.debian.org/security/2021/dsa-4844"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Third Party Advisory"], "url": "https://www.jsof-tech.com/disclosures/dnspooq/"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "url": "https://www.kb.cert.org/vuls/id/434904"}], "sourceIdentifier": "secalert@redhat.com", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-122"}], "source": "secalert@redhat.com", "type": "Secondary"}, {"description": [{"lang": "en", "value": "CWE-787"}], "source": "nvd@nist.gov", "type": "Secondary"}]}

{"acknowledgement": "Red Hat would like to thank Moshe Kol (JSOF) and Shlomi Oberman (JSOF) for reporting this issue.", "affected_release": [{"advisory": "RHSA-2021:0150", "cpe": "cpe:/a:redhat:enterprise_linux:8", "package": "dnsmasq-0:2.79-13.el8_3.1", "product_name": "Red Hat Enterprise Linux 8", "release_date": "2021-01-19T00:00:00Z"}, {"advisory": "RHSA-2021:0152", "cpe": "cpe:/a:redhat:rhel_eus:8.1", "package": "dnsmasq-0:2.79-6.el8_1.1", "product_name": "Red Hat Enterprise Linux 8.1 Extended Update Support", "release_date": "2021-01-19T00:00:00Z"}, {"advisory": "RHSA-2021:0151", "cpe": "cpe:/a:redhat:rhel_eus:8.2", "package": "dnsmasq-0:2.79-11.el8_2.2", "product_name": "Red Hat Enterprise Linux 8.2 Extended Update Support", "release_date": "2021-01-19T00:00:00Z"}], "bugzilla": {"description": "dnsmasq: buffer overflow in extract_name() due to missing length check when DNSSEC is enabled", "id": "1882014", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=1882014"}, "csaw": true, "cvss3": {"cvss3_base_score": "8.1", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H", "status": "verified"}, "cwe": "CWE-122", "details": ["A flaw was found in dnsmasq before 2.83. A buffer overflow vulnerability was discovered in the way dnsmasq extract names from DNS packets before validating them with DNSSEC data. An attacker on the network, who can create valid DNS replies, could use this flaw to cause an overflow with arbitrary data in a heap-allocated memory, possibly executing code on the machine. The flaw is in the rfc1035.c:extract_name() function, which writes data to the memory pointed by name assuming MAXDNAME*2 bytes are available in the buffer. However, in some code execution paths, it is possible extract_name() gets passed an offset from the base buffer, thus reducing, in practice, the number of available bytes that can be written in the buffer. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.", "A flaw was found in dnsmasq. A buffer overflow vulnerability was discovered in the way dnsmasq extract names from DNS packets before validating them with DNSSEC data. An attacker on the network, who can create valid DNS replies, could use this flaw to cause an overflow with arbitrary data in a heap-allocated memory, possibly executing code on the machine. The flaw is in the rfc1035.c:extract_name() function, which writes data to the memory pointed by name assuming MAXDNAME*2 bytes are available in the buffer. However, in some code execution paths, it is possible extract_name() gets passed an offset from the base buffer, thus reducing, in practice, the number of available bytes that can be written in the buffer. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability."], "mitigation": {"lang": "en:us", "value": "The only known way to mitigate this flaw is to disable DNSSEC altogether, by removing the `--dnssec` command line option or the `dnssec` option from dnsmasq configuration file."}, "name": "CVE-2020-25682", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:5", "fix_state": "Not affected", "package_name": "dnsmasq", "product_name": "Red Hat Enterprise Linux 5"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "dnsmasq", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "dnsmasq", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "dnsmasq", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:openstack:10", "fix_state": "Not affected", "package_name": "dnsmasq", "product_name": "Red Hat OpenStack Platform 10 (Newton)"}, {"cpe": "cpe:/a:redhat:openstack:13", "fix_state": "Not affected", "package_name": "dnsmasq", "product_name": "Red Hat OpenStack Platform 13 (Queens)"}], "public_date": "2021-01-19T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2020-25682\nhttps://nvd.nist.gov/vuln/detail/CVE-2020-25682\nhttps://www.jsof-tech.com/disclosures/dnspooq/"], "statement": "This issue does not affect the versions of dnsmasq as shipped with Red Hat Enterprise Linux 5, 6, and 7 as they are not compiled with DNSSEC support.", "threat_severity": "Important"}

{}