MediumFix available
firefox-esr, thunderbird — security advisory
When proxy auto-detection is enabled, if a web server serves a Proxy Auto-Configuration (PAC) file or if a PAC file is loaded locally, this PAC file can specify that requests to the localhost are to be sent through the proxy to another server. This behavior is disallowed by default when a proxy is manually configured, but when enabled could allow for attacks on services and tools that bind to the localhost for networked behavior if they are accessed through browsing. This vulnerability affects Firefox < 65.
- Products
- firefox-esr, thunderbird
- Affected versions
- Not specified
- Fixed versions
- 1:60.6.1-1, 60.6.0esr-1
- CVEs
- CVE-2018-18506
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 00:55 UTC · Revision 1
Source evidence
When proxy auto-detection is enabled, if a web server serves a Proxy Auto-Configuration (PAC) file or if a PAC file is loaded locally, this PAC file can specify that requests to the localhost are to be sent through the proxy to another server. This behavior is disallowed by default when a proxy is manually configured, but when enabled could allow for attacks on services and tools that bind to the localhost for networked behavior if they are accessed through browsing. This vulnerability affects Firefox < 65.
osv:DEBIAN-CVE-2018-18506
firefox-esr
Fixed versions: 60.6.0esr-1
firefox-esr
Fixed versions: 60.6.0esr-1
firefox-esr
Fixed versions: 60.6.0esr-1
thunderbird
Fixed versions: 1:60.6.1-1
thunderbird
Fixed versions: 1:60.6.1-1
thunderbird
Fixed versions: 1:60.6.1-1
Complete source record
{
"id": "0bb26d94f708ef253fcd6bd016381e0eaf21e11bca9b48f5f19eccc81683bc0c",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2018-18506",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2018-18506",
"summary": "When proxy auto-detection is enabled, if a web server serves a Proxy Auto-Configuration (PAC) file or if a PAC file is loaded locally, this PAC file can specify that requests to the localhost are to be sent through the proxy to another server. This behavior is disallowed by default when a proxy is manually configured, but when enabled could allow for attacks on services and tools that bind to the localhost for networked behavior if they are accessed through browsing. This vulnerability affects Firefox < 65.",
"evidence": "osv:DEBIAN-CVE-2018-18506",
"products": [
{
"name": {
"value": "firefox-esr",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "60.6.0esr-1",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "firefox-esr",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "60.6.0esr-1",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "firefox-esr",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "60.6.0esr-1",
"evidence": "/affected/2/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "thunderbird",
"evidence": "/affected/3/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:60.6.1-1",
"evidence": "/affected/3/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "thunderbird",
"evidence": "/affected/4/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:60.6.1-1",
"evidence": "/affected/4/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "thunderbird",
"evidence": "/affected/5/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:60.6.1-1",
"evidence": "/affected/5/ranges"
}
],
"affected_versions": []
}
],
"severity": "medium",
"structured": {
"id": "DEBIAN-CVE-2018-18506",
"aliases": [
"DEBIAN-CVE-2018-18506"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "60.6.0esr-1"
}
]
}
],
"package": {
"name": "firefox-esr",
"purl": "pkg:deb/debian/firefox-esr?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2018-18506.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "60.6.0esr-1"
}
]
}
],
"package": {
"name": "firefox-esr",
"purl": "pkg:deb/debian/firefox-esr?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2018-18506.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "60.6.0esr-1"
}
]
}
],
"package": {
"name": "firefox-esr",
"purl": "pkg:deb/debian/firefox-esr?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2018-18506.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:60.6.1-1"
}
]
}
],
"package": {
"name": "thunderbird",
"purl": "pkg:deb/debian/thunderbird?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2018-18506.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:60.6.1-1"
}
]
}
],
"package": {
"name": "thunderbird",
"purl": "pkg:deb/debian/thunderbird?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2018-18506.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:60.6.1-1"
}
]
}
],
"package": {
"name": "thunderbird",
"purl": "pkg:deb/debian/thunderbird?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2018-18506.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-23T18:03:56.390309427Z",
"provider": "osv",
"upstream": [
"CVE-2018-18506"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2018-18506"
]
},
"related_cves": [
{
"value": "CVE-2018-18506",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 422689,
"published_at": "2019-02-05T21:29:00.707+00:00"
}