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CVE-2018-6789
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…
Critical9.8Known exploitedEPSS 82.1%
- Published
- Updated
- Reserved
- Assigned by
- mitre
Description
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.
Exploited in the wild
CISA lists this vulnerability in its Known Exploited Vulnerabilities catalog as Exim Buffer Overflow Vulnerability.
- Added
- 3 Nov 2021
- Fix due (US federal)
- 3 May 2022
- Used by ransomware
- Known
Apply updates per vendor instructions.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| CISA-ADPADP (enrichment) | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Analyzed | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 82.1% · top 0.3% of all CVEs (3 Nov 2026)
- CISA SSVC
- Exploitation: active · Automatable: yes · Technical impact: total
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.8.
Weakness
Affected products
n/a
- affected n/a
References (14)
- https://exim.org/static/doc/security/CVE-2018-6789.txt (opens in a new tab)x_refsource_CONFIRMx_transferred
- [oss-security] 20180207 CVE-2018-6789 Exim 4.90 and earlier: buffer overflow (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- USN-3565-1 (opens in a new tab)vendor-advisoryx_refsource_UBUNTUx_transferred
- http://openwall.com/lists/oss-security/2018/02/10/2 (opens in a new tab)x_refsource_CONFIRMx_transferred
- 1040461 (opens in a new tab)vdb-entryx_refsource_SECTRACKx_transferred
- DSA-4110 (opens in a new tab)vendor-advisoryx_refsource_DEBIANx_transferred
- 44571 (opens in a new tab)exploitx_refsource_EXPLOIT-DBx_transferred
- [debian-lts-announce] 20180210 [SECURITY] [DLA 1274-1] exim4 security update (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- https://git.exim.org/exim.git/commit/cf3cd306062a08969c41a1cdd32c6855f1abecf1 (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://devco.re/blog/2018/03/06/exim-off-by-one-RCE-exploiting-CVE-2018-6789-en/ (opens in a new tab)x_refsource_MISCx_transferred
- 103049 (opens in a new tab)vdb-entryx_refsource_BIDx_transferred
- 45671 (opens in a new tab)exploitx_refsource_EXPLOIT-DBx_transferred
- http://packetstormsecurity.com/files/162959/Exim-base64d-Buffer-Overflow.html (opens in a new tab)x_refsource_MISCx_transferred
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2018-6789 (opens in a new tab)government-resource
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- CISA KEV catalog (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2018-6789)Record last updated .