CriticalFix available
apache2 — security advisory
It was found that the fix for CVE-2021-41773 in Apache HTTP Server 2.4.50 was insufficient. An attacker could use a path traversal attack to map URLs to files outside the directories configured by Alias-like directives. If files outside of these directories are not protected by the usual default configuration "require all denied", these requests can succeed. If CGI scripts are also enabled for these aliased pathes, this could allow for remote code execution. This issue only affects Apache 2.4.49 and Apache 2.4.50 and not earlier versions.
- Products
- apache2
- Affected versions
- Not specified
- Fixed versions
- 2.4.51-r0
- CVEs
- CVE-2021-42013
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 22:07 UTC · Revision 1
Source evidence
It was found that the fix for CVE-2021-41773 in Apache HTTP Server 2.4.50 was insufficient. An attacker could use a path traversal attack to map URLs to files outside the directories configured by Alias-like directives. If files outside of these directories are not protected by the usual default configuration "require all denied", these requests can succeed. If CGI scripts are also enabled for these aliased pathes, this could allow for remote code execution. This issue only affects Apache 2.4.49 and Apache 2.4.50 and not earlier versions.
osv:ALPINE-CVE-2021-42013
apache2
Fixed versions: 2.4.51-r0
apache2
Fixed versions: 2.4.51-r0
apache2
Fixed versions: 2.4.51-r0
apache2
Fixed versions: 2.4.51-r0
apache2
Fixed versions: 2.4.51-r0
apache2
Fixed versions: 2.4.51-r0
apache2
Fixed versions: 2.4.51-r0
apache2
Fixed versions: 2.4.51-r0
apache2
Fixed versions: 2.4.51-r0
apache2
Fixed versions: 2.4.51-r0
apache2
Fixed versions: 2.4.51-r0
apache2
Fixed versions: 2.4.51-r0
apache2
Fixed versions: 2.4.51-r0
apache2
Fixed versions: 2.4.51-r0
Complete source record
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],
"modified": "2026-10-23T17:17:56.217356615Z",
"provider": "osv",
"upstream": [
"CVE-2021-42013"
],
"references": [
"https://security.alpinelinux.org/vuln/CVE-2021-42013"
]
},
"related_cves": [
{
"value": "CVE-2021-42013",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 415572,
"published_at": "2021-10-07T16:15:09.27+00:00"
}