When using LookupCNAME with the cgo DNS resolver, a very long CNAME response can trigger a double-free of C memory and a crash.
{
"unresolved_ranges": [
{
"source": "AFFECTED_FIELD",
"extracted_events": [
{
"fixed": "1.25.10"
},
{
"introduced": "1.26.0-0"
},
{
"fixed": "1.26.3"
}
]
}
],
"cna_assigner": "Go",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33811.json"
}{
"source": "CPE_FIELD",
"extracted_events": [
{
"introduced": "0"
},
{
"fixed": "1.25.10"
},
{
"introduced": "1.26.0"
},
{
"fixed": "1.26.3"
}
],
"cpe": "cpe:2.3:a:golang:go:*:*:*:*:*:*:*:*"
}