A denial of service vulnerability exists in curl <v8.1.0 in the way libcurl provides several different backends for resolving host names, selected at build time. If it is built to use the synchronous resolver, it allows name resolves to time-out slow operations using alarm() and siglongjmp(). When doing this, libcurl used a global buffer that was not mutex protected and a multi-threaded application might therefore crash or otherwise misbehave.
{
"license": "CC-BY-4.0",
"sources": [
{
"imported": "2026-05-02T08:39:47.037Z",
"id": "CVE-2023-28320",
"published": "2023-05-26T21:15:15.937Z",
"url": "https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2023-28320",
"database_specific": {
"status": "Modified"
},
"modified": "2025-01-15T16:15:25.953Z",
"html_url": "https://nvd.nist.gov/vuln/detail/CVE-2023-28320"
}
]
}