The intx509paramsethosts function in lib/libcrypto/x509/x509_vpm.c in LibreSSL 2.7.0 before 2.7.1 does not support a certain special case of a zero name length, which causes silent omission of hostname verification, and consequently allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate. NOTE: the LibreSSL documentation indicates that this special case is supported, but the BoringSSL documentation does not.
{
"unresolved_ranges": [
{
"source": "CPE_STRING",
"cpes": [
"cpe:2.3:a:openbsd:libressl:2.7.0:*:*:*:*:*:*:*"
],
"vendor_product": "openbsd:libressl",
"extracted_events": [
{
"introduced": "2.7.0"
},
{
"last_affected": "2.7.0"
}
]
}
]
}[
{
"digest": {
"length": 675.0,
"function_hash": "124066432240387748490862556255300495937"
},
"signature_version": "v1",
"source": "https://github.com/libressl/openbsd/commit/0654414afcce51a16d35d05060190a3ec4618d42",
"signature_type": "Function",
"target": {
"function": "int_x509_param_set_hosts",
"file": "src/lib/libcrypto/x509/x509_vpm.c"
},
"id": "CVE-2018-8970-1fc07437",
"deprecated": false
},
{
"digest": {
"threshold": 0.9,
"line_hashes": [
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},
"signature_version": "v1",
"source": "https://github.com/libressl/openbsd/commit/0654414afcce51a16d35d05060190a3ec4618d42",
"signature_type": "Line",
"target": {
"file": "src/lib/libcrypto/x509/x509_vpm.c"
},
"id": "CVE-2018-8970-3ec5e240",
"deprecated": false
}
]
"2026-07-08T20:15:31Z"
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2018-8970.json"