Medium
Security advisory
In Go before 1.15.13 and 1.16.x before 1.16.5, some configurations of ReverseProxy (from net/http/httputil) result in a situation where an attacker is able to drop arbitrary headers.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2021-33197
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 05:39 UTC · Revision 1
Source evidence
In Go before 1.15.13 and 1.16.x before 1.16.5, some configurations of ReverseProxy (from net/http/httputil) result in a situation where an attacker is able to drop arbitrary headers.
osv:CVE-2021-33197
Complete source record
{
"id": "c037488febe7024a28e1b0d7bf3103aaf44d4e7b43b7062e6e35f741388b969e",
"url": "https://osv.dev/vulnerability/CVE-2021-33197",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2021-33197",
"summary": "In Go before 1.15.13 and 1.16.x before 1.16.5, some configurations of ReverseProxy (from net/http/httputil) result in a situation where an attacker is able to drop arbitrary headers.",
"evidence": "osv:CVE-2021-33197",
"products": [],
"severity": "medium",
"structured": {
"id": "CVE-2021-33197",
"aliases": [
"BIT-golang-2021-33197",
"CVE-2021-33197",
"GO-2021-0241"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/golang/go",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"fixed": "ab7f8297f9734b24a43a942930258cda411f16a3"
},
{
"fixed": "7677616a263e8ded606cc8297cb67ddc667a876e"
}
],
"database_specific": {
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{
"cpe": "cpe:2.3:a:golang:go:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"fixed": "1.15.13"
}
],
"source": "CPE_RANGE"
},
{
"cpe": "cpe:2.3:a:golang:go:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "1.16.0"
},
{
"fixed": "1.16.5"
}
],
"source": "CPE_RANGE"
}
]
}
}
],
"versions": [
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"go1.15.12",
"go1.15.11",
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"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-33197.json"
}
}
],
"modified": "2026-10-24T10:30:31.999459337Z",
"provider": "osv",
"references": [
"https://groups.google.com/g/golang-announce",
"https://security.gentoo.org/glsa/202208-02",
"https://groups.google.com/g/golang-announce/c/RgCMkAEQjSI"
],
"provider_metadata": {}
},
"related_cves": [
{
"value": "CVE-2021-33197",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 432924,
"published_at": "2021-08-02T19:15:08.493+00:00"
}