MediumFix available
squid — security advisory
An issue was discovered in Squid before 4.15 and 5.x before 5.0.6. Due to an input-validation bug, it is vulnerable to a Denial of Service attack (against all clients using the proxy). A client sends an HTTP Range request to trigger this.
- Products
- squid
- Affected versions
- Not specified
- Fixed versions
- 4.15-r0, 5.0.6-r0
- CVEs
- CVE-2021-31808
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 22:04 UTC · Revision 1
Source evidence
An issue was discovered in Squid before 4.15 and 5.x before 5.0.6. Due to an input-validation bug, it is vulnerable to a Denial of Service attack (against all clients using the proxy). A client sends an HTTP Range request to trigger this.
osv:ALPINE-CVE-2021-31808
squid
Fixed versions: 4.15-r0
squid
Fixed versions: 4.15-r0
squid
Fixed versions: 4.15-r0
squid
Fixed versions: 5.0.6-r0
squid
Fixed versions: 5.0.6-r0
squid
Fixed versions: 5.0.6-r0
squid
Fixed versions: 5.0.6-r0
squid
Fixed versions: 5.0.6-r0
squid
Fixed versions: 5.0.6-r0
squid
Fixed versions: 5.0.6-r0
squid
Fixed versions: 5.0.6-r0
squid
Fixed versions: 5.0.6-r0
squid
Fixed versions: 5.0.6-r0
squid
Fixed versions: 5.0.6-r0
squid
Fixed versions: 5.0.6-r0
Complete source record
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],
"modified": "2026-10-23T17:17:56.186176151Z",
"provider": "osv",
"upstream": [
"CVE-2021-31808"
],
"references": [
"https://security.alpinelinux.org/vuln/CVE-2021-31808"
]
},
"related_cves": [
{
"value": "CVE-2021-31808",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 415435,
"published_at": "2021-05-27T14:15:07.5+00:00"
}