exim4 — security advisory
Exim Improper Neutralization of Special Elements Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of Exim. Authentication is not required to exploit this vulnerability. The specific flaw exists within the smtp service, which listens on TCP port 25 by default. The issue results from the lack of proper validation of user-supplied data, which can result in a memory corruption condition. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-17554.
- Products
- exim4
- Affected versions
- 4.96-15, 4.96-15+deb12u1, 4.96-15+deb12u2
- Fixed versions
- 4.96-15+deb12u3, 4.97~RC2-2
- CVEs
- CVE-2023-42117
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 15:58 UTC · Revision 1
Source evidence
Exim Improper Neutralization of Special Elements Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of Exim. Authentication is not required to exploit this vulnerability. The specific flaw exists within the smtp service, which listens on TCP port 25 by default. The issue results from the lack of proper validation of user-supplied data, which can result in a memory corruption condition. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-17554.
osv:DEBIAN-CVE-2023-42117
exim4
Fixed versions: 4.96-15+deb12u3
exim4
Fixed versions: 4.97~RC2-2
exim4
Fixed versions: 4.97~RC2-2
Complete source record
{
"id": "f93be5506ef03ee84a9e8236580d94dbf075997306976f5ef883872f1dca7320",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2023-42117",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2023-42117",
"summary": "Exim Improper Neutralization of Special Elements Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of Exim. Authentication is not required to exploit this vulnerability. The specific flaw exists within the smtp service, which listens on TCP port 25 by default. The issue results from the lack of proper validation of user-supplied data, which can result in a memory corruption condition. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-17554.",
"evidence": "osv:DEBIAN-CVE-2023-42117",
"products": [
{
"name": {
"value": "exim4",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "4.96-15+deb12u3",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": [
{
"value": "4.96-15",
"evidence": "/affected/0/versions"
},
{
"value": "4.96-15+deb12u1",
"evidence": "/affected/0/versions"
},
{
"value": "4.96-15+deb12u2",
"evidence": "/affected/0/versions"
}
]
},
{
"name": {
"value": "exim4",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "4.97~RC2-2",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": []
},
{
"name": {
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},
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"fixed_versions": [
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}
],
"severity": "critical",
"structured": {
"id": "DEBIAN-CVE-2023-42117",
"aliases": [
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],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "4.96-15+deb12u3"
}
]
}
],
"package": {
"name": "exim4",
"purl": "pkg:deb/debian/exim4?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
"4.96-15",
"4.96-15+deb12u1",
"4.96-15+deb12u2"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2023-42117.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "4.97~RC2-2"
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}
],
"package": {
"name": "exim4",
"purl": "pkg:deb/debian/exim4?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2023-42117.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "4.97~RC2-2"
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}
],
"package": {
"name": "exim4",
"purl": "pkg:deb/debian/exim4?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2023-42117.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-26T18:02:32.770483401Z",
"provider": "osv",
"upstream": [
"CVE-2023-42117"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2023-42117"
]
},
"related_cves": [
{
"value": "CVE-2023-42117",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 456229,
"published_at": "2024-05-03T03:15:50.463+00:00"
}