Description (CNA)
A vulnerability in libcurl caused the HTTP `Referer:` header to persist even when explicitly cleared. While the documentation states that passing NULL to `CURLOPT_REFERER` suppresses the header, the option failed to clear the internal state. As a result, the previous referrer string was erroneously reused and sent in subsequent requests, potentially leaking sensitive information to unintended servers.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| curl / curl | affected 8.18.0 before 8.20.1 |
| curl / curl | affected 2cb868242dc2ac9cd52ee64987ef51d5964a56f9 before 862e8a74a84478d82973471b4f49dc2746c1780e |
| curl / curl | affected 8.20.0; affected 8.19.0; affected 8.18.0 |
CWE
CWE-200
References
- https://curl.se/docs/CVE-2026-9546.json
- https://curl.se/docs/CVE-2026-9546.html
- https://hackerone.com/reports/3754343
ADP enrichment
No English description supplied.