libexpat before 2.8.2 has an integer overflow in copyString.
{
"cna_assigner": "mitre",
"cwe_ids": [
"CWE-190"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/56xxx/CVE-2026-56408.json"
}{
"cpe": "cpe:2.3:a:libexpat_project:libexpat:*:*:*:*:*:*:*:*",
"extracted_events": [
{
"introduced": "0"
},
{
"fixed": "2.8.2"
}
],
"source": [
"CPE_RANGE",
"REFERENCES"
]
}
"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-56408.json"
[
{
"deprecated": false,
"digest": {
"line_hashes": [
"49764371326105024949167023033929323404",
"331886275670177522007581575306208215313",
"47859046433447248635562634368972807069"
],
"threshold": 0.9
},
"id": "CVE-2026-56408-49af9273",
"signature_type": "Line",
"signature_version": "v1",
"source": "https://github.com/libexpat/libexpat/commit/16e2efd867ea8567ffa012210b52ef5918e20817",
"target": {
"file": "expat/lib/xmlparse.c"
}
},
{
"deprecated": false,
"digest": {
"function_hash": "304819910357209817028662367993368572534",
"length": 276
},
"id": "CVE-2026-56408-bb252a66",
"signature_type": "Function",
"signature_version": "v1",
"source": "https://github.com/libexpat/libexpat/commit/16e2efd867ea8567ffa012210b52ef5918e20817",
"target": {
"file": "expat/lib/xmlparse.c",
"function": "copyString"
}
}
]
"2026-08-18T18:39:38Z"