certfr_avis - certfr-2024-avi-0054

CERTFR-2024-AVI-0054

Vulnerability from certfr_avis

Une vulnérabilité a été découverte dans Exim. Elle permet à un attaquant de provoquer un contournement de la politique de sécurité.

Solution

Se référer au bulletin de sécurité de l'éditeur pour l'obtention des correctifs (cf. section Documentation).

None

Impacted products

	Vendor	Product	Description
	Exim	N/A	Exim versions antérieures à 4.97.1

References

Title

Publication Time

CVE-2023-51766 (GCVE-0-2023-51766)

Vulnerability from cvelistv5

Published

2023-12-24 00:00

Modified

2025-11-04 18:21

Severity ?

CWE

Summary

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.

References

URL

Tags

	https://sec-consult.com/blog/detail/smtp-smuggling-spoofing-e-mails-worldwide/
	https://exim.org/static/doc/security/CVE-2023-51766.txt
	https://bugs.exim.org/show_bug.cgi?id=3063
	https://www.openwall.com/lists/oss-security/2023/12/23/2
	http://www.openwall.com/lists/oss-security/2023/12/24/1	mailing-list
	http://www.openwall.com/lists/oss-security/2023/12/25/1	mailing-list
	https://git.exim.org/exim.git/commit/5bb786d5ad568a88d50d15452aacc8404047e5ca
	https://git.exim.org/exim.git/commit/cf1376206284f2a4f11e32d931d4aade34c206c5
	https://bugzilla.redhat.com/show_bug.cgi?id=2255852
	https://fahrplan.events.ccc.de/congress/2023/fahrplan/events/11782.html
	http://www.openwall.com/lists/oss-security/2023/12/29/2	mailing-list
	https://github.com/Exim/exim/blob/master/doc/doc-txt/cve-2023-51766
	http://www.openwall.com/lists/oss-security/2024/01/01/1	mailing-list
	http://www.openwall.com/lists/oss-security/2024/01/01/2	mailing-list
	http://www.openwall.com/lists/oss-security/2024/01/01/3	mailing-list
	https://www.youtube.com/watch?v=V8KPV96g1To
	https://lists.debian.org/debian-lts-announce/2024/01/msg00002.html	mailing-list
	https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QPDWHJPABVJCXDSNELSSVTIVAJU2MDUQ/	vendor-advisory
	https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ORN7OKEQPPBKUHYRQ6LR5PSNBQVDHAWB/	vendor-advisory
	https://lwn.net/Articles/956533/

Impacted products

	Vendor	Product	Version
	n/a	n/a	Version: n/a

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date

Nomenclature

Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
Confirmed: The vulnerability is confirmed from an analyst perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
Patched: This vulnerability was successfully patched by the user reporting the sighting.
Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
Not confirmed: The user expresses doubt about the veracity of the vulnerability.
Not patched: This vulnerability was not successfully patched by the user reporting the sighting.

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