CVE-2026-86409
Published: October 17, 2026Last modified: October 21, 2026
Description
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.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 8.1 |
| Attack Vector | NETWORK |
| Attack complexity | HIGH |
| Privileges required | NONE |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | HIGH |
| Integrity impact | HIGH |
| Availability impact | HIGH |
| Vector | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | curl | Fixed (8.22.0-r0) |
| 25 LTS | curl | Fixed (8.22.0-r0) | |
| Stream | curl | Fixed (8.22.0-r0) | |
| Hardened Containers | Stream | curl | Fixed (8.22.0-r0) |