Exploitation evidence
Known exploited · CISA KEV listed
Added 2021-11-03. Ransomware campaign use: Known.
CISA required action: Apply updates per vendor instructions.
CISA due date: 2022-05-03. This is the catalog’s deadline, not an assessment of your organization’s exposure.
KEV checked 13 Nov 2026, 00:20 Jerusalem · Original catalog ↗Reported products and versions
n/a / n/a
Default status: Not specified
- affected: n/a
Fixes and workarounds
No explicit solution text in the downloaded CVE record. Consult the vendor advisory; unaffected version ranges are shown above as reported, not inferred as a patch recommendation.
Sources and related reporting
CVE Program record ↗ · Download tracked evidence as JSON
- https://exim.org/static/doc/security/CVE-2018-6789.txt
- http://www.openwall.com/lists/oss-security/2018/02/07/2
- https://usn.ubuntu.com/3565-1/
- http://openwall.com/lists/oss-security/2018/02/10/2
- http://www.securitytracker.com/id/1040461
- https://www.debian.org/security/2018/dsa-4110
- https://www.exploit-db.com/exploits/44571/
- https://lists.debian.org/debian-lts-announce/2018/02/msg00009.html
- https://git.exim.org/exim.git/commit/cf3cd306062a08969c41a1cdd32c6855f1abecf1
- https://devco.re/blog/2018/03/06/exim-off-by-one-RCE-exploiting-CVE-2018-6789-en/
- http://www.securityfocus.com/bid/103049
- https://www.exploit-db.com/exploits/45671/
- http://packetstormsecurity.com/files/162959/Exim-base64d-Buffer-Overflow.html
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2018-6789
Observed change timeline
History begins when Egret first downloads each source. It is not the complete upstream CVE history.
12 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-12",
"epss": 0.82137,
"percentile": 0.99662
}10 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-10",
"epss": 0.82137,
"percentile": 0.9966
}09 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-09",
"epss": 0.82137,
"percentile": 0.99659
}08 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-08",
"epss": 0.82137,
"percentile": 0.99659
}07 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-07",
"epss": 0.82137,
"percentile": 0.99658
}07 Nov 2026, 00:20 Jerusalem · CVE Program record changed
Stored CNA snapshot at this observation.
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}06 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-06",
"epss": 0.82137,
"percentile": 0.99659
}05 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-05",
"epss": 0.82137,
"percentile": 0.99658
}04 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-04",
"epss": 0.82137,
"percentile": 0.99657
}03 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-03",
"epss": 0.82137,
"percentile": 0.99656
}03 Nov 2026, 02:22 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-02",
"epss": 0.82137,
"percentile": 0.99655
}03 Nov 2026, 02:22 Jerusalem · CISA KEV status changed
Stored KEV snapshot at this observation.
{
"cveID": "CVE-2018-6789",
"cwes": [
"CWE-119"
],
"dateAdded": "2021-11-03",
"dueDate": "2022-05-03",
"forensicTriage": "No",
"knownRansomwareCampaignUse": "Known",
"notes": "https://nvd.nist.gov/vuln/detail/CVE-2018-6789",
"product": "Exim",
"requiredAction": "Apply updates per vendor instructions.",
"shortDescription": "Exim contains a buffer overflow vulnerability in the base64d function part of the SMTP listener that may allow for remote code execution.",
"vendorProject": "Exim",
"vulnerabilityName": "Exim Buffer Overflow Vulnerability"
}