HighFix available
apache2 — security advisory
A crafted method sent through HTTP/2 will bypass validation and be forwarded by mod_proxy, which can lead to request splitting or cache poisoning. This issue affects Apache HTTP Server 2.4.17 to 2.4.48.
- Products
- apache2
- Affected versions
- Not specified
- Fixed versions
- 2.4.49-r0
- CVEs
- CVE-2021-33193
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 22:05 UTC · Revision 1
Source evidence
A crafted method sent through HTTP/2 will bypass validation and be forwarded by mod_proxy, which can lead to request splitting or cache poisoning. This issue affects Apache HTTP Server 2.4.17 to 2.4.48.
osv:ALPINE-CVE-2021-33193
apache2
Fixed versions: 2.4.49-r0
apache2
Fixed versions: 2.4.49-r0
apache2
Fixed versions: 2.4.49-r0
apache2
Fixed versions: 2.4.49-r0
apache2
Fixed versions: 2.4.49-r0
apache2
Fixed versions: 2.4.49-r0
apache2
Fixed versions: 2.4.49-r0
apache2
Fixed versions: 2.4.49-r0
apache2
Fixed versions: 2.4.49-r0
apache2
Fixed versions: 2.4.49-r0
apache2
Fixed versions: 2.4.49-r0
apache2
Fixed versions: 2.4.49-r0
apache2
Fixed versions: 2.4.49-r0
apache2
Fixed versions: 2.4.49-r0
Complete source record
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],
"modified": "2026-10-23T17:17:56.190043214Z",
"provider": "osv",
"upstream": [
"CVE-2021-33193"
],
"references": [
"https://security.alpinelinux.org/vuln/CVE-2021-33193"
]
},
"related_cves": [
{
"value": "CVE-2021-33193",
"evidence": "/upstream"
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],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 415455,
"published_at": "2021-08-16T08:15:11.48+00:00"
}