Vulnerability-Lookup

CNVD-2018-04619

Vulnerability from cnvd - Published: 2018-03-08

Title

Exim SMTP Mail Server缓冲区溢出漏洞

Description

Exim是一个MTA（Mail Transfer Agent，邮件传输代理）服务器软件，该软件基于GPL协议开发，是一款开源软件。该软件主要运行于类UNIX系统。通常该软件会与Dovecot或Courier等软件搭配使用。 Exim 4.90.1之前版本中的SMTPSMTP侦听器'base64d()'解码函数在发送handcrafted消息时存在缓冲区溢出漏洞，攻击者可利用该漏洞在受影响的应用程序上下文中执行任意代码，若攻击尝试失败仍可导致拒绝服务条件。

Severity

高

Patch Name

Exim SMTP Mail Server缓冲区溢出漏洞的补丁

Patch Description

Exim是在剑桥大学开发的消息传输代理（MTA），用于连接到互联网的Unix系统。 Exim 4.90.1之前版本中的SMTP侦听器'base64d()'解码函数在发送handcrafted消息时存在缓冲区溢出漏洞，攻击者可利用该漏洞在受影响的应用程序上下文中执行任意代码，若攻击尝试失败仍可导致拒绝服务条件。目前，供应商发布了安全公告及相关补丁信息，修复了此漏洞。

Formal description

目前厂商已经发布了升级补丁以修复此安全问题，补丁获取链接： https://devco.re/blog/2018/03/06/exim-off-by-one-RCE-exploiting-CVE-2018-6789-en/

Reference

https://nvd.nist.gov/vuln/detail/CVE-2018-6789

Impacted products

Name
Exim Exim <4.90.1

Show details on source website

JSON

To clipboard

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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

JSON

To clipboard

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            {
              "name": "http://packetstormsecurity.com/files/162959/Exim-base64d-Buffer-Overflow.html",
              "refsource": "MISC",
              "url": "http://packetstormsecurity.com/files/162959/Exim-base64d-Buffer-Overflow.html"
            }
          ]
        }
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
    "assignerShortName": "mitre",
    "cveId": "CVE-2018-6789",
    "datePublished": "2018-02-08T23:00:00.000Z",
    "dateReserved": "2018-02-06T00:00:00.000Z",
    "dateUpdated": "2025-10-21T23:45:56.260Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1"
}

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.