CVE-2023-51766
Estado: ModificadaMedia (5.3)—
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.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
- Puntuación base: 5.3
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 1.10%
- Percentil entre todas las CVEs puntuadas: 65
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (4)
CWE
- CWE-345
Referencias
- http://www.openwall.com/lists/oss-security/2023/12/24/1
- http://www.openwall.com/lists/oss-security/2023/12/25/1
- http://www.openwall.com/lists/oss-security/2023/12/29/2
- http://www.openwall.com/lists/oss-security/2024/01/01/1
- http://www.openwall.com/lists/oss-security/2024/01/01/2
- http://www.openwall.com/lists/oss-security/2024/01/01/3
- https://bugs.exim.org/show_bug.cgi?id=3063
- https://bugzilla.redhat.com/show_bug.cgi?id=2255852
- https://exim.org/static/doc/security/CVE-2023-51766.txt
- https://fahrplan.events.ccc.de/congress/2023/fahrplan/events/11782.html
- https://git.exim.org/exim.git/commit/5bb786d5ad568a88d50d15452aacc8404047e5ca
- https://git.exim.org/exim.git/commit/cf1376206284f2a4f11e32d931d4aade34c206c5
- https://github.com/Exim/exim/blob/master/doc/doc-txt/cve-2023-51766
- https://lists.debian.org/debian-lts-announce/2024/01/msg00002.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ORN7OKEQPPBKUHYRQ6LR5PSNBQVDHAWB/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QPDWHJPABVJCXDSNELSSVTIVAJU2MDUQ/
- https://lwn.net/Articles/956533/
- https://sec-consult.com/blog/detail/smtp-smuggling-spoofing-e-mails-worldwide/
- https://www.openwall.com/lists/oss-security/2023/12/23/2
- https://www.youtube.com/watch?v=V8KPV96g1To
- http://www.openwall.com/lists/oss-security/2023/12/24/1
- http://www.openwall.com/lists/oss-security/2023/12/25/1
- http://www.openwall.com/lists/oss-security/2023/12/29/2
- http://www.openwall.com/lists/oss-security/2024/01/01/1
- http://www.openwall.com/lists/oss-security/2024/01/01/2
- http://www.openwall.com/lists/oss-security/2024/01/01/3
- https://bugs.exim.org/show_bug.cgi?id=3063
- https://bugzilla.redhat.com/show_bug.cgi?id=2255852
- https://exim.org/static/doc/security/CVE-2023-51766.txt
- https://fahrplan.events.ccc.de/congress/2023/fahrplan/events/11782.html
- https://git.exim.org/exim.git/commit/5bb786d5ad568a88d50d15452aacc8404047e5ca
- https://git.exim.org/exim.git/commit/cf1376206284f2a4f11e32d931d4aade34c206c5
- https://github.com/Exim/exim/blob/master/doc/doc-txt/cve-2023-51766
- https://lists.debian.org/debian-lts-announce/2024/01/msg00002.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ORN7OKEQPPBKUHYRQ6LR5PSNBQVDHAWB/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QPDWHJPABVJCXDSNELSSVTIVAJU2MDUQ/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ORN7OKEQPPBKUHYRQ6LR5PSNBQVDHAWB/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/QPDWHJPABVJCXDSNELSSVTIVAJU2MDUQ/
- https://lwn.net/Articles/956533/
- https://sec-consult.com/blog/detail/smtp-smuggling-spoofing-e-mails-worldwide/
- https://www.openwall.com/lists/oss-security/2023/12/23/2
- https://www.youtube.com/watch?v=V8KPV96g1To
JSON original (NVD)
Mostrar
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"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."
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}
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"lastModified": "2026-06-17T06:41:37.057",
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