CVE-2026-86409
Last modified
CVE-2026-86409 is a high-severity vulnerability rated 8.1/10 on the CVSS scale. 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.. EPSS estimates a 0.31% chance of exploitation in the next 30 days.
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.
Metrics
Weakness Enumeration
Affected Software
Source: CNA advisory (CVE.org). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| curl | curl | >= 8.21.0, <= 8.21.0; >= 8.20.0, <= 8.20.0; >= 8.19.0, <= 8.19.0; >= 8.18.0, <= 8.18.0; >= 8.17.0, <= 8.17.0; >= 8.16.0, <= 8.16.0; >= 8.15.0, <= 8.15.0; >= 8.14.1, <= 8.14.1; >= 8.14.0, <= 8.14.0; >= 8.13.0, <= 8.13.0; >= 8.12.1, <= 8.12.1; >= 8.12.0, <= 8.12.0; >= 8.11.1, <= 8.11.1; >= 8.11.0, <= 8.11.0; >= 8.10.1, <= 8.10.1; >= 8.10.0, <= 8.10.0; >= 8.9.1, <= 8.9.1; >= 8.9.0, <= 8.9.0; >= 8.8.0, <= 8.8.0; >= 8.7.1, <= 8.7.1; >= 8.7.0, <= 8.7.0; >= 8.6.0, <= 8.6.0; >= 8.5.0, <= 8.5.0; >= 8.4.0, <= 8.4.0; >= 8.3.0, <= 8.3.0; >= 8.2.1, <= 8.2.1; >= 8.2.0, <= 8.2.0; >= 8.1.2, <= 8.1.2; >= 8.1.1, <= 8.1.1; >= 8.1.0, <= 8.1.0; >= 8.0.1, <= 8.0.1; >= 8.0.0, <= 8.0.0; >= 7.88.1, <= 7.88.1; >= 7.88.0, <= 7.88.0; >= 7.87.0, <= 7.87.0; >= 7.86.0, <= 7.86.0; >= 7.85.0, <= 7.85.0; >= 7.84.0, <= 7.84.0; >= 7.83.1, <= 7.83.1; >= 7.83.0, <= 7.83.0; >= 7.82.0, <= 7.82.0; >= 7.81.0, <= 7.81.0; >= 7.80.0, <= 7.80.0; >= 7.79.1, <= 7.79.1; >= 7.79.0, <= 7.79.0; >= 7.78.0, <= 7.78.0; >= 7.77.0, <= 7.77.0; >= 7.76.1, <= 7.76.1; >= 7.76.0, <= 7.76.0; >= 7.75.0, <= 7.75.0 |
References
Timeline
- Published
- Last Modified
- Status
- Awaiting Analysis
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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