The "go tool pack" subcommand (usually used only by the compiler as an internal tool with known-good inputs) does not sanitize output filenames. Extracting a malicious archive file with the "pack" subcommand can write files to arbitrary locations on the filesystem.
{
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/39xxx/CVE-2026-39817.json",
"cna_assigner": "Go",
"unresolved_ranges": [
{
"extracted_events": [
{
"fixed": "1.25.10"
},
{
"introduced": "1.26.0-0"
},
{
"fixed": "1.26.3"
}
],
"source": "AFFECTED_FIELD"
}
]
}{
"extracted_events": [
{
"introduced": "0"
},
{
"fixed": "1.25.10"
},
{
"introduced": "1.26.0"
},
{
"fixed": "1.26.3"
}
],
"source": "CPE_FIELD",
"cpe": "cpe:2.3:a:golang:go:*:*:*:*:*:*:*:*"
}