USN-8486-1
- Source
- https://ubuntu.com/security/notices/USN-8486-1
- Import Source
- https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8486-1.json
- JSON Data
- https://api.osv.dev/v1/vulns/USN-8486-1
- Upstream
- Related
- Published
- 2026-06-30T12:41:51Z
- Modified
- 2026-07-01T23:32:46.286503436Z
- Summary
- libssh2 vulnerabilities
- Details
-
It was discovered that libssh2 incorrectly handled the sftp_symlink() function. A malicious SSH server or machine-in-the-middle attacker could possibly use this issue to obtain sensitive information or cause a denial of service. (CVE-2025-15661)
It was discovered that libssh2 had a pre-authentication denial of service vulnerability in the SSHMSGEXT_INFO handler. A malicious SSH server could possibly use this issue to cause a client CPU exhaustion loop, resulting in a denial of service. (CVE-2026-55199)
It was discovered that libssh2 incorrectly handled packet length fields. A remote attacker could possibly use this issue to execute arbitrary code. This issue only affected Ubuntu 25.10 and Ubuntu 26.04 LTS. (CVE-2026-55200)
- References
Affected packages
Ubuntu:24.04:LTS / libssh2
Package
- Name
- libssh2
- Purl
- pkg:deb/ubuntu/libssh2?arch=source&distro=noble
Affected ranges
- Type
- ECOSYSTEM
- Events
-
Introduced0Unknown introduced version / All previous versions are affectedFixed1.11.0-4.1ubuntu0.24.04.2
Affected versions
1.*
1.11.0-2
1.11.0-3
1.11.0-4
1.11.0-4.1build1
1.11.0-4.1build2
1.11.0-4.1ubuntu0.24.04.1
Ecosystem specific
{
"binaries": [
{
"binary_name": "libssh2-1t64",
"binary_version": "1.11.0-4.1ubuntu0.24.04.2"
}
],
"availability": "No subscription required"
}
Database specific
source
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8486-1.json"
cves_map
{
"ecosystem": "Ubuntu:24.04:LTS",
"cves": [
{
"id": "CVE-2025-15661",
"severity": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H"
},
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H"
},
{
"type": "CVSS_V4",
"score": "CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N"
},
{
"type": "Ubuntu",
"score": "medium"
}
]
},
{
"id": "CVE-2026-55199",
"severity": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H"
},
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
},
{
"type": "CVSS_V4",
"score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"
},
{
"type": "Ubuntu",
"score": "medium"
}
]
}
]
}
Ubuntu:25.10 / libssh2
Package
- Name
- libssh2
- Purl
- pkg:deb/ubuntu/libssh2?arch=source&distro=questing
Affected ranges
- Type
- ECOSYSTEM
- Events
-
Introduced0Unknown introduced version / All previous versions are affectedFixed1.11.1-1ubuntu0.25.10.2
Ecosystem specific
{
"binaries": [
{
"binary_name": "libssh2-1t64",
"binary_version": "1.11.1-1ubuntu0.25.10.2"
}
],
"availability": "No subscription required"
}
Database specific
source
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8486-1.json"
cves_map
{
"ecosystem": "Ubuntu:25.10",
"cves": [
{
"id": "CVE-2025-15661",
"severity": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H"
},
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H"
},
{
"type": "CVSS_V4",
"score": "CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N"
},
{
"type": "Ubuntu",
"score": "medium"
}
]
},
{
"id": "CVE-2026-55199",
"severity": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H"
},
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
},
{
"type": "CVSS_V4",
"score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"
},
{
"type": "Ubuntu",
"score": "medium"
}
]
},
{
"id": "CVE-2026-55200",
"severity": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H"
},
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L"
},
{
"type": "CVSS_V4",
"score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"
},
{
"type": "Ubuntu",
"score": "medium"
}
]
}
]
}
Ubuntu:26.04:LTS / libssh2
Package
- Name
- libssh2
- Purl
- pkg:deb/ubuntu/libssh2?arch=source&distro=resolute
Affected ranges
- Type
- ECOSYSTEM
- Events
-
Introduced0Unknown introduced version / All previous versions are affectedFixed1.11.1-1ubuntu0.26.04.2
Ecosystem specific
{
"binaries": [
{
"binary_name": "libssh2-1t64",
"binary_version": "1.11.1-1ubuntu0.26.04.2"
}
],
"availability": "No subscription required"
}
Database specific
source
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8486-1.json"
cves_map
{
"ecosystem": "Ubuntu:26.04:LTS",
"cves": [
{
"id": "CVE-2025-15661",
"severity": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H"
},
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H"
},
{
"type": "CVSS_V4",
"score": "CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N"
},
{
"type": "Ubuntu",
"score": "medium"
}
]
},
{
"id": "CVE-2026-55199",
"severity": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H"
},
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
},
{
"type": "CVSS_V4",
"score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"
},
{
"type": "Ubuntu",
"score": "medium"
}
]
},
{
"id": "CVE-2026-55200",
"severity": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H"
},
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L"
},
{
"type": "CVSS_V4",
"score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"
},
{
"type": "Ubuntu",
"score": "medium"
}
]
}
]
}