Vulnerability-Lookup

CERTFR-2018-ALE-004

Vulnerability from certfr_alerte - Published: 2018-03-07 - Updated: 2018-07-30

Le 5 février 2018, la société de sécurité Devcore a informé l'éditeur du serveur de messagerie Exim d'une vulnérabilité dans leur produit. Cette vulnérabilité identifiée en tant que CVE-2018-6789 permet à un attaquant de provoquer une exécution de code arbitraire à distance sur un serveur Exim vulnérable.

La CVE-2018-6789 exploite une faille de type débordement de mémoire sur un seul octet ("off-by-one") présente dans toutes les versions du serveur de messagerie pour compromettre l'application. Les détails techniques sur la vulnérabilité ont par ailleurs fait l'objet d'une publication le 6 mars 2018 par le chercheur en sécurité à l'origine de cette découverte (cf. section Documentation).

Solution

La version 4.90.1, disponible depuis le 10 février 2018, intègre le correctif de sécurité pour la vulnérabilité CVE-2018-6789.

Le CERT-FR recommande la mise à jour immédiate d'Exim.

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 toutes versions antérieures à 4.90.1

References

Title

Publication Time

CVE-2018-6789 (GCVE-0-2018-6789)

Vulnerability from cvelistv5 – Published: 2018-02-08 23:00 – Updated: 2025-10-21 23:45

Summary

An issue was discovered in the base64d function in the SMTP listener in Exim before 4.90.1. By sending a handcrafted message, a buffer overflow may happen. This can be used to execute code remotely.

Severity

9.8 (Critical)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

SSVC

Exploitation: active Automatable: yes Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2025-02-07 14:03 UTC

CWE

n/a
CWE-120 - Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

Assigner

mitre mitre root

References

14 references

URL	Tags
https://exim.org/static/doc/security/CVE-2018-6789.txt	x_refsource_CONFIRM
http://www.openwall.com/lists/oss-security/2018/02/07/2	mailing-listx_refsource_MLIST
https://usn.ubuntu.com/3565-1/	vendor-advisoryx_refsource_UBUNTU
http://openwall.com/lists/oss-security/2018/02/10/2	x_refsource_CONFIRM
http://www.securitytracker.com/id/1040461	vdb-entryx_refsource_SECTRACK
https://www.debian.org/security/2018/dsa-4110	vendor-advisoryx_refsource_DEBIAN
https://www.exploit-db.com/exploits/44571/	exploitx_refsource_EXPLOIT-DB
https://lists.debian.org/debian-lts-announce/2018…	mailing-listx_refsource_MLIST
https://git.exim.org/exim.git/commit/cf3cd306062a…	x_refsource_CONFIRM
https://devco.re/blog/2018/03/06/exim-off-by-one-…	x_refsource_MISC
http://www.securityfocus.com/bid/103049	vdb-entryx_refsource_BID
https://www.exploit-db.com/exploits/45671/	exploitx_refsource_EXPLOIT-DB
http://packetstormsecurity.com/files/162959/Exim-…	x_refsource_MISC
https://www.cisa.gov/known-exploited-vulnerabilit…	government-resource

Date Public

2018-02-07 00:00

Show details on NVD website

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.