CVEvulnerability
CVE-2026-9546
7.5 HIGH
Official page ↗
- Status
- Modified
- Published
- 2026-07-03
- Last modified
- 2026-09-15
- Assigner
- 2499f714-1537-4658-8207-48ae4bb9eae9
- CVSS 3.1 (134c704f-9b21-4f2e-91b3-4a467353bcc0)
- 7.5 HIGH — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- Weaknesses
- CWE-200
Description
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 configurations
• haxx curl (>= 8.18.0 < 8.21.0)
Related
Weakness · CWE (1)
- CWE-200 Exposure of Sensitive Information to an Unauthorized Actor weakness
References
- https://curl.se/docs/CVE-2026-9546.html Patch, Vendor Advisory
- https://curl.se/docs/CVE-2026-9546.json Third Party Advisory
- https://hackerone.com/reports/3754343 Exploit, Issue Tracking, Third Party Advisory
- https://hackerone.com/reports/3754343 Exploit, Issue Tracking, Third Party Advisory