CVE-2023-51766

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{"affected": [{"affectedData": [{"product": "n/a", "vendor": "n/a", "versions": [{"status": "affected", "version": "n/a"}]}], "source": "cve@mitre.org"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:exim:exim:*:*:*:*:*:*:*:*", "matchCriteriaId": "95F6F151-E57F-4DB2-9CCD-3336B887A07B", "versionEndExcluding": "4.97.1", "vulnerable": true}], "negate": false, "operator": "OR"}]}, {"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:fedoraproject:extra_packages_for_enterprise_linux:7.0:*:*:*:*:*:*:*", "matchCriteriaId": "3D9C7598-4BB4-442A-86DF-EEDE041A4CC7", "vulnerable": true}, {"criteria": "cpe:2.3:a:fedoraproject:extra_packages_for_enterprise_linux:8.0:*:*:*:*:*:*:*", "matchCriteriaId": "BB176AC3-3CDA-4DDA-9089-C67B2F73AA62", "vulnerable": true}, {"criteria": "cpe:2.3:a:fedoraproject:extra_packages_for_enterprise_linux:9.0:*:*:*:*:*:*:*", "matchCriteriaId": "3C30C1AC-01E4-4D7C-B03A-8EEEF3FC8C2F", "vulnerable": true}, {"criteria": "cpe:2.3:o:fedoraproject:fedora:38:*:*:*:*:*:*:*", "matchCriteriaId": "CC559B26-5DFC-4B7A-A27C-B77DE755DFF9", "vulnerable": true}, {"criteria": "cpe:2.3:o:fedoraproject:fedora:39:*:*:*:*:*:*:*", "matchCriteriaId": "B8EDB836-4E6A-4B71-B9B2-AA3E03E0F646", "vulnerable": true}], "negate": false, "operator": "OR"}]}, {"nodes": [{"cpeMatch": [{"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": "Exim before 4.97.1 allows SMTP smuggling in certain PIPELINING/CHUNKING configurations. Remote attackers can use a published exploitation technique to inject e-mail messages with a spoofed MAIL FROM address, allowing bypass of an SPF protection mechanism. This occurs because Exim supports <LF>.<CR><LF> but some other popular e-mail servers do not."}, {"lang": "es", "value": "Exim hasta 4.97 permite el contrabando SMTP en ciertas configuraciones. Los atacantes remotos pueden utilizar una t\u00e9cnica de explotaci\u00f3n publicada para inyectar mensajes de correo electr\u00f3nico que parecen originarse en el servidor Exim, permitiendo omitir un mecanismo de protecci\u00f3n SPF. Esto ocurre porque Exim admite . pero algunos otros servidores de correo electr\u00f3nico populares no lo hacen."}], "id": "CVE-2023-51766", "lastModified": "2026-06-17T06:41:37.057", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 5.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "LOW", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 1.4, "source": "nvd@nist.gov", "type": "Primary"}]}, "published": "2023-12-24T06:15:07.673", "references": [{"source": "cve@mitre.org", "tags": ["Mailing List", "Third Party Advisory"], "url": "http://www.openwall.com/lists/oss-security/2023/12/24/1"}, {"source": "cve@mitre.org", "tags": ["Mailing List", "Third Party Advisory"], "url": 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