UnratedFix available
curl — security advisory
When libcurl uses libssh2 with a hashed `known_hosts` file, an unrelated initial entry can cause host key validation to report a key *mismatch* as a *missing* key to the `CURLOPT_SSH_KEYFUNCTION` callback.
- Products
- curl
- Affected versions
- 8.14.1-2ubuntu1, 8.17.0-1ubuntu1, 8.18.0-1ubuntu1, 8.18.0-1ubuntu2, 8.18.0-1ubuntu2.1, 8.18.0-1ubuntu2.2, 8.18.0-1ubuntu2.3, 8.18.0-1ubuntu2.4, 8.18.0-1ubuntu2.5, 8.18.0-1ubuntu2.7, 8.20.0-2ubuntu1, 8.20.0-2ubuntu10, 8.20.0-2ubuntu11, 8.20.0-2ubuntu3
- Fixed versions
- 8.18.0-1ubuntu2.8, 8.20.0-2ubuntu11.1
- CVEs
- CVE-2026-87865
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 08:45 UTC · Revision 1
Source evidence
When libcurl uses libssh2 with a hashed `known_hosts` file, an unrelated initial entry can cause host key validation to report a key *mismatch* as a *missing* key to the `CURLOPT_SSH_KEYFUNCTION` callback.
osv:UBUNTU-CVE-2026-87865
curl
Fixed versions: 8.20.0-2ubuntu11.1
curl
Fixed versions: 8.18.0-1ubuntu2.8
Complete source record
{
"id": "87ad552a8067a8a6d199621e99ed682034944448d1e7387201212a15ba90fb03",
"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-87865",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "UBUNTU-CVE-2026-87865",
"summary": "When libcurl uses libssh2 with a hashed `known_hosts` file, an unrelated initial entry can cause host key validation to report a key *mismatch* as a *missing* key to the `CURLOPT_SSH_KEYFUNCTION` callback.",
"evidence": "osv:UBUNTU-CVE-2026-87865",
"products": [
{
"name": {
"value": "curl",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "8.20.0-2ubuntu11.1",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": [
{
"value": "8.18.0-1ubuntu2",
"evidence": "/affected/0/versions"
},
{
"value": "8.20.0-2ubuntu1",
"evidence": "/affected/0/versions"
},
{
"value": "8.20.0-2ubuntu3",
"evidence": "/affected/0/versions"
},
{
"value": "8.20.0-2ubuntu10",
"evidence": "/affected/0/versions"
},
{
"value": "8.20.0-2ubuntu11",
"evidence": "/affected/0/versions"
}
]
},
{
"name": {
"value": "curl",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "8.18.0-1ubuntu2.8",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": [
{
"value": "8.14.1-2ubuntu1",
"evidence": "/affected/1/versions"
},
{
"value": "8.17.0-1ubuntu1",
"evidence": "/affected/1/versions"
},
{
"value": "8.18.0-1ubuntu1",
"evidence": "/affected/1/versions"
},
{
"value": "8.18.0-1ubuntu2",
"evidence": "/affected/1/versions"
},
{
"value": "8.18.0-1ubuntu2.1",
"evidence": "/affected/1/versions"
},
{
"value": "8.18.0-1ubuntu2.2",
"evidence": "/affected/1/versions"
},
{
"value": "8.18.0-1ubuntu2.3",
"evidence": "/affected/1/versions"
},
{
"value": "8.18.0-1ubuntu2.4",
"evidence": "/affected/1/versions"
},
{
"value": "8.18.0-1ubuntu2.5",
"evidence": "/affected/1/versions"
},
{
"value": "8.18.0-1ubuntu2.7",
"evidence": "/affected/1/versions"
}
]
}
],
"severity": "unknown",
"structured": {
"id": "UBUNTU-CVE-2026-87865",
"aliases": [
"UBUNTU-CVE-2026-87865"
],
"metrics": [
{
"type": "Ubuntu",
"score": "low"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "8.20.0-2ubuntu11.1"
}
]
}
],
"package": {
"name": "curl",
"purl": "pkg:deb/ubuntu/curl?arch=source&distro=stonking",
"ecosystem": "Ubuntu:26.10"
},
"versions": [
"8.18.0-1ubuntu2",
"8.20.0-2ubuntu1",
"8.20.0-2ubuntu3",
"8.20.0-2ubuntu10",
"8.20.0-2ubuntu11"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-87865.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "curl",
"binary_version": "8.20.0-2ubuntu11.1"
},
{
"binary_name": "libcurl3t64-gnutls",
"binary_version": "8.20.0-2ubuntu11.1"
},
{
"binary_name": "libcurl4t64",
"binary_version": "8.20.0-2ubuntu11.1"
}
],
"availability": "No subscription required",
"priority_reason": "Upstream defined this as low severity"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "8.18.0-1ubuntu2.8"
}
]
}
],
"package": {
"name": "curl",
"purl": "pkg:deb/ubuntu/curl?arch=source&distro=resolute",
"ecosystem": "Ubuntu:26.04:LTS"
},
"versions": [
"8.14.1-2ubuntu1",
"8.17.0-1ubuntu1",
"8.18.0-1ubuntu1",
"8.18.0-1ubuntu2",
"8.18.0-1ubuntu2.1",
"8.18.0-1ubuntu2.2",
"8.18.0-1ubuntu2.3",
"8.18.0-1ubuntu2.4",
"8.18.0-1ubuntu2.5",
"8.18.0-1ubuntu2.7"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-87865.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "curl",
"binary_version": "8.18.0-1ubuntu2.8"
},
{
"binary_name": "libcurl3t64-gnutls",
"binary_version": "8.18.0-1ubuntu2.8"
},
{
"binary_name": "libcurl4t64",
"binary_version": "8.18.0-1ubuntu2.8"
}
],
"availability": "No subscription required",
"priority_reason": "Upstream defined this as low severity"
}
}
],
"modified": "2026-10-19T23:42:07.151189621Z",
"provider": "osv",
"upstream": [
"CVE-2026-87865"
],
"references": [
"https://ubuntu.com/security/CVE-2026-87865",
"https://www.cve.org/CVERecord?id=CVE-2026-87865",
"https://curl.se/docs/CVE-2026-87865.html",
"https://ubuntu.com/security/notices/USN-8927-1",
"https://ubuntu.com/security/notices/USN-8927-2"
]
},
"related_cves": [
{
"value": "CVE-2026-87865",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": null
},
"source_id": "core-osv",
"document_id": 376853,
"published_at": "2026-10-14T06:00:00+00:00"
}