High
Security advisory
An issue was discovered in Squid 4.0.23 through 4.7. When checking Basic Authentication with HttpHeader::getAuth, Squid uses a global buffer to store the decoded data. Squid does not check that the decoded length isn't greater than the buffer, leading to a heap-based buffer overflow with user controlled data.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2019-12527
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 10:45 UTC · Revision 1
Source evidence
An issue was discovered in Squid 4.0.23 through 4.7. When checking Basic Authentication with HttpHeader::getAuth, Squid uses a global buffer to store the decoded data. Squid does not check that the decoded length isn't greater than the buffer, leading to a heap-based buffer overflow with user controlled data.
osv:CVE-2019-12527
Complete source record
{
"id": "e513657210f53e8e21a63d07f31ece134b1167e131b4270586a7f6c029fe5654",
"url": "https://osv.dev/vulnerability/CVE-2019-12527",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2019-12527",
"summary": "An issue was discovered in Squid 4.0.23 through 4.7. When checking Basic Authentication with HttpHeader::getAuth, Squid uses a global buffer to store the decoded data. Squid does not check that the decoded length isn't greater than the buffer, leading to a heap-based buffer overflow with user controlled data.",
"evidence": "osv:CVE-2019-12527",
"products": [],
"severity": "high",
"structured": {
"id": "CVE-2019-12527",
"aliases": [
"CVE-2019-12527"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/squid-cache/squid",
"type": "GIT",
"events": [
{
"introduced": "787b41c3b0ef9b7330032a1947c5f93bd050f32a"
},
{
"last_affected": "2e17b02616d37206ba9cccc53c20667624fbef9f"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "4.0.23"
},
{
"last_affected": "4.7"
}
],
"source": "CPE_RANGE"
}
]
}
}
],
"versions": [
"SQUID_4_7",
"SQUID_4_6",
"SQUID_4_5",
"SQUID_4_4",
"SQUID_4_3",
"SQUID_4_2",
"SQUID_4_1",
"SQUID_4_0_25",
"SQUID_4_0_24",
"SQUID_4_0_23"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2019-12527.json"
}
}
],
"modified": "2026-10-20T10:51:36.674801259Z",
"provider": "osv",
"references": [
"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SPXN2CLAGN5QSQBTOV5IGVLDOQSRFNTZ/",
"https://access.redhat.com/errata/RHSA-2019:2593",
"https://seclists.org/bugtraq/2019/Aug/42",
"https://usn.ubuntu.com/4065-1/",
"https://www.debian.org/security/2019/dsa-4507",
"https://github.com/squid-cache/squid/commits/v4"
],
"provider_metadata": {
"unresolved_ranges": [
{
"cpes": [
"cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:esm:*:*:*",
"cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*",
"cpe:2.3:o:canonical:ubuntu_linux:19.04:*:*:*:*:*:*:*"
],
"vendor_product": "canonical:ubuntu_linux",
"extracted_events": [
{
"range": [
{
"introduced": "16.04"
},
{
"last_affected": "16.04"
},
{
"introduced": "18.04"
},
{
"last_affected": "18.04"
},
{
"introduced": "19.04"
},
{
"last_affected": "19.04"
}
],
"source": "CPE_STRING"
}
]
},
{
"cpes": [
"cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*"
],
"vendor_product": "debian:debian_linux",
"extracted_events": [
{
"range": [
{
"introduced": "10.0"
},
{
"last_affected": "10.0"
}
],
"source": "CPE_STRING"
}
]
},
{
"cpes": [
"cpe:2.3:o:fedoraproject:fedora:29:*:*:*:*:*:*:*"
],
"vendor_product": "fedoraproject:fedora",
"extracted_events": [
{
"range": [
{
"introduced": "29"
},
{
"last_affected": "29"
}
],
"source": "CPE_STRING"
}
]
},
{
"cpes": [
"cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*"
],
"vendor_product": "redhat:enterprise_linux",
"extracted_events": [
{
"range": [
{
"introduced": "8.0"
},
{
"last_affected": "8.0"
}
],
"source": "CPE_STRING"
}
]
},
{
"cpes": [
"cpe:2.3:o:redhat:enterprise_linux_eus:8.1:*:*:*:*:*:*:*",
"cpe:2.3:o:redhat:enterprise_linux_eus:8.2:*:*:*:*:*:*:*",
"cpe:2.3:o:redhat:enterprise_linux_eus:8.4:*:*:*:*:*:*:*",
"cpe:2.3:o:redhat:enterprise_linux_eus:8.6:*:*:*:*:*:*:*"
],
"vendor_product": "redhat:enterprise_linux_eus",
"extracted_events": [
{
"range": [
{
"introduced": "8.1"
},
{
"last_affected": "8.1"
},
{
"introduced": "8.2"
},
{
"last_affected": "8.2"
},
{
"introduced": "8.4"
},
{
"last_affected": "8.4"
},
{
"introduced": "8.6"
},
{
"last_affected": "8.6"
}
],
"source": "CPE_STRING"
}
]
},
{
"cpes": [
"cpe:2.3:o:redhat:enterprise_linux_server_aus:8.2:*:*:*:*:*:*:*",
"cpe:2.3:o:redhat:enterprise_linux_server_aus:8.4:*:*:*:*:*:*:*",
"cpe:2.3:o:redhat:enterprise_linux_server_aus:8.6:*:*:*:*:*:*:*"
],
"vendor_product": "redhat:enterprise_linux_server_aus",
"extracted_events": [
{
"range": [
{
"introduced": "8.2"
},
{
"last_affected": "8.2"
},
{
"introduced": "8.4"
},
{
"last_affected": "8.4"
},
{
"introduced": "8.6"
},
{
"last_affected": "8.6"
}
],
"source": "CPE_STRING"
}
]
},
{
"cpes": [
"cpe:2.3:o:redhat:enterprise_linux_server_tus:8.2:*:*:*:*:*:*:*",
"cpe:2.3:o:redhat:enterprise_linux_server_tus:8.4:*:*:*:*:*:*:*",
"cpe:2.3:o:redhat:enterprise_linux_server_tus:8.6:*:*:*:*:*:*:*"
],
"vendor_product": "redhat:enterprise_linux_server_tus",
"extracted_events": [
{
"range": [
{
"introduced": "8.2"
},
{
"last_affected": "8.2"
},
{
"introduced": "8.4"
},
{
"last_affected": "8.4"
},
{
"introduced": "8.6"
},
{
"last_affected": "8.6"
}
],
"source": "CPE_STRING"
}
]
}
]
}
},
"related_cves": [
{
"value": "CVE-2019-12527",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 382640,
"published_at": "2019-07-11T19:15:13.097+00:00"
}