CVE-2026-6276
7.5 · HIGHOverview
CVE-2026-6276 is a high-severity vulnerability affecting haxx curl. It was published on May 13, 2026 and has a CVSS 3.1 base score of 7.5 (HIGH).
This vulnerability has a CVSS 3.1 base score of 7.5, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
Using libcurl, when a custom `Host:` header is first set for an HTTP request
and a second request is subsequently done using the same *easy handle* but
without the custom `Host:` header set, the second request would use stale
information and pass on cookies meant for the first host in the second
request. Leak them.
Remediation
Check the references section for vendor advisories and patches from haxx. Update curl to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| haxx | curl | >= 7.71.0, < 8.20.0 | Affected |
Frequently Asked Questions
What is CVE-2026-6276?
CVE-2026-6276 is a high-severity vulnerability affecting haxx curl. It was published on May 13, 2026 and has a CVSS 3.1 base score of 7.5 (HIGH).
How severe is CVE-2026-6276?
This vulnerability has a CVSS 3.1 base score of 7.5, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-6276?
Check the references section for vendor advisories and patches from haxx. Update curl to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-6276?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-6276 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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