UBUNTU-CVE-2021-23351 (CVE-2021-23351)
Vulnerability from osv_ubuntu – Published: 2021-03-08 05:15 – Updated: 2025-09-08 16:46 – Source websiteThe package github.com/pires/go-proxyproto before 0.5.0 are vulnerable to Denial of Service (DoS) via the parseVersion1() function. The reader in this package is a default bufio.Reader wrapping a net.Conn. It will read from the connection until it finds a newline. Since no limits are implemented in the code, a deliberately malformed V1 header could be used to exhaust memory in a server process using this code - and create a DoS. This can be exploited by sending a stream starting with PROXY and continuing to send data (which does not contain a newline) until the target stops acknowledging. The risk here is small, because only trusted sources should be allowed to send proxy protocol headers.
{
"affected": [
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "golang-github-pires-go-proxyproto-dev",
"binary_version": "0.4.2-1"
}
]
},
"package": {
"ecosystem": "Ubuntu:22.04:LTS",
"name": "golang-github-pires-go-proxyproto",
"purl": "pkg:deb/ubuntu/golang-github-pires-go-proxyproto@0.4.2-1?arch=source\u0026distro=jammy"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"0.4.2-1"
]
}
],
"aliases": [],
"details": "The package github.com/pires/go-proxyproto before 0.5.0 are vulnerable to Denial of Service (DoS) via the parseVersion1() function. The reader in this package is a default bufio.Reader wrapping a net.Conn. It will read from the connection until it finds a newline. Since no limits are implemented in the code, a deliberately malformed V1 header could be used to exhaust memory in a server process using this code - and create a DoS. This can be exploited by sending a stream starting with PROXY and continuing to send data (which does not contain a newline) until the target stops acknowledging. The risk here is small, because only trusted sources should be allowed to send proxy protocol headers.",
"id": "UBUNTU-CVE-2021-23351",
"modified": "2025-09-08T16:46:59Z",
"published": "2021-03-08T05:15:00Z",
"references": [
{
"type": "REPORT",
"url": "https://ubuntu.com/security/CVE-2021-23351"
},
{
"type": "REPORT",
"url": "https://github.com/pires/go-proxyproto/commit/7f48261db810703d173f27f3309a808cc2b49b8b"
},
{
"type": "REPORT",
"url": "https://github.com/pires/go-proxyproto/issues/69"
},
{
"type": "REPORT",
"url": "https://github.com/pires/go-proxyproto/pull/71"
},
{
"type": "REPORT",
"url": "https://snyk.io/vuln/SNYK-GOLANG-GITHUBCOMPIRESGOPROXYPROTO-1081577"
},
{
"type": "REPORT",
"url": "https://www.cve.org/CVERecord?id=CVE-2021-23351"
}
],
"related": [],
"schema_version": "1.7.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
},
{
"score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
},
{
"score": "medium",
"type": "Ubuntu"
}
],
"upstream": [
"CVE-2021-23351"
]
}
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|---|
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