compress provides various compression algorithms. Prior to version 1.18.7, a signed integer overflow vulnerability in s2.NewDict() allows an attacker to bypass repeat index validation by supplying a dictionary with a uvarint-encoded repeat value exceeding MaxInt64. When Dict.Encode() is subsequently called, the overflowed negative repeat value causes an out-of-bounds memory access via unsafe.Pointer arithmetic, crashing the process with SIGSEGV. This issue has been patched in version 1.18.7.
{
"cna_assigner": "GitHub_M",
"cwe_ids": [
"CWE-190",
"CWE-787"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63209.json"
}{
"extracted_events": [
{
"range": [
{
"introduced": "0"
},
{
"fixed": "1.18.7"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StringRangeExpression"
},
{
"range": [
{
"fixed": "539243b8823ee8f03e49969823d57c348c917536"
}
],
"source": "REFERENCES_COMMIT"
},
{
"original_tag": "v1.18.7",
"range": [
{
"fixed": "8668e357e776d5152ed62f33c17f21b8690664fa"
}
],
"source": "REFERENCES_TAG"
}
]
}