CVE-2026-86409 — stale SigV4 headers sent unintended
Setting `CURLOPT_AWS_SIGV4` to NULL but does not disable SigV4 authentication, contrary to expectations and documentation. A subsequent transfer on the same handle still sends a…
Published: 2026-10-20 · CVSS: Unscored
Setting `CURLOPT_AWS_SIGV4` to NULL but does not disable SigV4 authentication, contrary to expectations and documentation. A subsequent transfer on the same handle still sends an `Authorization: AWS4-HMAC-SHA256` header to whatever URL isset next, leaking state information.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7