UBUNTU-CVE-2021-22876 (CVE-2021-22876)
Vulnerability from osv_ubuntu – Published: 2021-03-31 06:00 – Updated: 2026-04-22 07:39 – Source websitecurl 7.1.1 to and including 7.75.0 is vulnerable to an "Exposure of Private Personal Information to an Unauthorized Actor" by leaking credentials in the HTTP Referer: header. libcurl does not strip off user credentials from the URL when automatically populating the Referer: HTTP request header field in outgoing HTTP requests, and therefore risks leaking sensitive data to the server that is the target of the second HTTP request.
{
"affected": [
{
"ecosystem_specific": {
"availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
"binaries": [
{
"binary_name": "curl",
"binary_version": "7.35.0-1ubuntu2.20+esm7"
},
{
"binary_name": "libcurl3",
"binary_version": "7.35.0-1ubuntu2.20+esm7"
},
{
"binary_name": "libcurl3-gnutls",
"binary_version": "7.35.0-1ubuntu2.20+esm7"
},
{
"binary_name": "libcurl3-nss",
"binary_version": "7.35.0-1ubuntu2.20+esm7"
}
]
},
"package": {
"ecosystem": "Ubuntu:Pro:14.04:LTS",
"name": "curl",
"purl": "pkg:deb/ubuntu/curl@7.35.0-1ubuntu2.20+esm7?arch=source\u0026distro=trusty/esm"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "7.35.0-1ubuntu2.20+esm7"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"7.32.0-1ubuntu1",
"7.33.0-1ubuntu1",
"7.34.0-1ubuntu1",
"7.35.0-1ubuntu1",
"7.35.0-1ubuntu2",
"7.35.0-1ubuntu2.1",
"7.35.0-1ubuntu2.2",
"7.35.0-1ubuntu2.3",
"7.35.0-1ubuntu2.5",
"7.35.0-1ubuntu2.6",
"7.35.0-1ubuntu2.7",
"7.35.0-1ubuntu2.8",
"7.35.0-1ubuntu2.9",
"7.35.0-1ubuntu2.10",
"7.35.0-1ubuntu2.11",
"7.35.0-1ubuntu2.12",
"7.35.0-1ubuntu2.13",
"7.35.0-1ubuntu2.14",
"7.35.0-1ubuntu2.15",
"7.35.0-1ubuntu2.16",
"7.35.0-1ubuntu2.17",
"7.35.0-1ubuntu2.19",
"7.35.0-1ubuntu2.20",
"7.35.0-1ubuntu2.20+esm2",
"7.35.0-1ubuntu2.20+esm3",
"7.35.0-1ubuntu2.20+esm4",
"7.35.0-1ubuntu2.20+esm5",
"7.35.0-1ubuntu2.20+esm6"
]
},
{
"ecosystem_specific": {
"availability": "No subscription required",
"binaries": [
{
"binary_name": "curl",
"binary_version": "7.47.0-1ubuntu2.19"
},
{
"binary_name": "libcurl3",
"binary_version": "7.47.0-1ubuntu2.19"
},
{
"binary_name": "libcurl3-gnutls",
"binary_version": "7.47.0-1ubuntu2.19"
},
{
"binary_name": "libcurl3-nss",
"binary_version": "7.47.0-1ubuntu2.19"
}
]
},
"package": {
"ecosystem": "Ubuntu:16.04:LTS",
"name": "curl",
"purl": "pkg:deb/ubuntu/curl@7.47.0-1ubuntu2.19?arch=source\u0026distro=xenial"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "7.47.0-1ubuntu2.19"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"7.43.0-1ubuntu2",
"7.45.0-1ubuntu1",
"7.46.0-1ubuntu1",
"7.47.0-1ubuntu1",
"7.47.0-1ubuntu2",
"7.47.0-1ubuntu2.1",
"7.47.0-1ubuntu2.2",
"7.47.0-1ubuntu2.3",
"7.47.0-1ubuntu2.4",
"7.47.0-1ubuntu2.5",
"7.47.0-1ubuntu2.6",
"7.47.0-1ubuntu2.7",
"7.47.0-1ubuntu2.8",
"7.47.0-1ubuntu2.9",
"7.47.0-1ubuntu2.11",
"7.47.0-1ubuntu2.12",
"7.47.0-1ubuntu2.13",
"7.47.0-1ubuntu2.14",
"7.47.0-1ubuntu2.15",
"7.47.0-1ubuntu2.16",
"7.47.0-1ubuntu2.18"
]
},
{
"ecosystem_specific": {
"availability": "No subscription required",
"binaries": [
{
"binary_name": "curl",
"binary_version": "7.58.0-2ubuntu3.13"
},
{
"binary_name": "libcurl3-gnutls",
"binary_version": "7.58.0-2ubuntu3.13"
},
{
"binary_name": "libcurl3-nss",
"binary_version": "7.58.0-2ubuntu3.13"
},
{
"binary_name": "libcurl4",
"binary_version": "7.58.0-2ubuntu3.13"
}
]
},
"package": {
"ecosystem": "Ubuntu:18.04:LTS",
"name": "curl",
"purl": "pkg:deb/ubuntu/curl@7.58.0-2ubuntu3.13?arch=source\u0026distro=bionic"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "7.58.0-2ubuntu3.13"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"7.55.1-1ubuntu2",
"7.55.1-1ubuntu2.1",
"7.57.0-1ubuntu1",
"7.58.0-2ubuntu1",
"7.58.0-2ubuntu2",
"7.58.0-2ubuntu3",
"7.58.0-2ubuntu3.1",
"7.58.0-2ubuntu3.2",
"7.58.0-2ubuntu3.3",
"7.58.0-2ubuntu3.5",
"7.58.0-2ubuntu3.6",
"7.58.0-2ubuntu3.7",
"7.58.0-2ubuntu3.8",
"7.58.0-2ubuntu3.9",
"7.58.0-2ubuntu3.10",
"7.58.0-2ubuntu3.12"
]
},
{
"ecosystem_specific": {
"availability": "No subscription required",
"binaries": [
{
"binary_name": "curl",
"binary_version": "7.68.0-1ubuntu2.5"
},
{
"binary_name": "libcurl3-gnutls",
"binary_version": "7.68.0-1ubuntu2.5"
},
{
"binary_name": "libcurl3-nss",
"binary_version": "7.68.0-1ubuntu2.5"
},
{
"binary_name": "libcurl4",
"binary_version": "7.68.0-1ubuntu2.5"
}
]
},
"package": {
"ecosystem": "Ubuntu:20.04:LTS",
"name": "curl",
"purl": "pkg:deb/ubuntu/curl@7.68.0-1ubuntu2.5?arch=source\u0026distro=focal"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "7.68.0-1ubuntu2.5"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"7.65.3-1ubuntu3",
"7.65.3-1ubuntu4",
"7.66.0-1ubuntu1",
"7.67.0-2ubuntu1",
"7.68.0-1ubuntu1",
"7.68.0-1ubuntu2",
"7.68.0-1ubuntu2.1",
"7.68.0-1ubuntu2.2",
"7.68.0-1ubuntu2.4"
]
}
],
"aliases": [],
"details": "curl 7.1.1 to and including 7.75.0 is vulnerable to an \"Exposure of Private Personal Information to an Unauthorized Actor\" by leaking credentials in the HTTP Referer: header. libcurl does not strip off user credentials from the URL when automatically populating the Referer: HTTP request header field in outgoing HTTP requests, and therefore risks leaking sensitive data to the server that is the target of the second HTTP request.",
"id": "UBUNTU-CVE-2021-22876",
"modified": "2026-04-22T07:39:55Z",
"published": "2021-03-31T06:00:00Z",
"references": [
{
"type": "REPORT",
"url": "https://ubuntu.com/security/CVE-2021-22876"
},
{
"type": "REPORT",
"url": "https://curl.se/docs/CVE-2021-22876.html"
},
{
"type": "ADVISORY",
"url": "https://ubuntu.com/security/notices/USN-4898-1"
},
{
"type": "ADVISORY",
"url": "https://ubuntu.com/security/notices/USN-4903-1"
},
{
"type": "REPORT",
"url": "https://www.cve.org/CVERecord?id=CVE-2021-22876"
}
],
"related": [
"USN-4898-1",
"USN-4903-1"
],
"schema_version": "1.7.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
"type": "CVSS_V3"
},
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
"type": "CVSS_V3"
},
{
"score": "medium",
"type": "Ubuntu"
}
],
"upstream": [
"CVE-2021-22876"
]
}
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