MediumFix available
curl — security advisory
An authentication bypass vulnerability exists in libcurl prior to v8.0.0 where it reuses a previously established SSH connection despite the fact that an SSH option was modified, which should have prevented reuse. libcurl maintains a pool of previously used connections to reuse them for subsequent transfers if the configurations match. However, two SSH settings were omitted from the configuration check, allowing them to match easily, potentially leading to the reuse of an inappropriate connection.
- Products
- curl
- Affected versions
- Not specified
- Fixed versions
- 7.88.1-r1, 8.0.0-r0, 8.0.1-r0
- CVEs
- CVE-2023-27538
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 14:56 UTC · Revision 1
Source evidence
An authentication bypass vulnerability exists in libcurl prior to v8.0.0 where it reuses a previously established SSH connection despite the fact that an SSH option was modified, which should have prevented reuse. libcurl maintains a pool of previously used connections to reuse them for subsequent transfers if the configurations match. However, two SSH settings were omitted from the configuration check, allowing them to match easily, potentially leading to the reuse of an inappropriate connection.
osv:ALPINE-CVE-2023-27538
curl
Fixed versions: 8.0.1-r0
curl
Fixed versions: 8.0.1-r0
curl
Fixed versions: 8.0.1-r0
curl
Fixed versions: 7.88.1-r1
curl
Fixed versions: 8.0.0-r0
curl
Fixed versions: 8.0.0-r0
curl
Fixed versions: 8.0.0-r0
curl
Fixed versions: 8.0.0-r0
curl
Fixed versions: 8.0.0-r0
curl
Fixed versions: 8.0.0-r0
curl
Fixed versions: 8.0.0-r0
Complete source record
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"modified": "2026-10-26T17:17:58.617091277Z",
"provider": "osv",
"upstream": [
"CVE-2023-27538"
],
"references": [
"https://security.alpinelinux.org/vuln/CVE-2023-27538"
]
},
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{
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],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 454410,
"published_at": "2023-03-30T20:15:07.677+00:00"
}