Vulnerability Description
An issue in curl’s QUIC UDP receive function allows a malicious HTTP/3 server to trigger a remote denial of service against a curl or libcurl client. Because the helper function discards zero-length UDP datagrams before counting them toward the per-call packet budget, a connected QUIC peer can continuously stream empty datagrams to indefinitely stall the client.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Haxx | Curl | >= 8.18.0, < 8.21.0 |
Related Weaknesses (CWE)
References
- https://curl.se/docs/CVE-2026-11352.htmlPatchVendor Advisory
- https://curl.se/docs/CVE-2026-11352.jsonVendor Advisory
- https://hackerone.com/reports/3783438ExploitIssue TrackingThird Party Advisory
- https://hackerone.com/reports/3783438ExploitIssue TrackingThird Party Advisory
FAQ
What is CVE-2026-11352?
CVE-2026-11352 is a vulnerability with a CVSS score of 7.5 (HIGH). An issue in curl’s QUIC UDP receive function allows a malicious HTTP/3 server to trigger a remote denial of service against a curl or libcurl client. Because the helper function discards zero-length U...
How severe is CVE-2026-11352?
CVE-2026-11352 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-11352?
Check the references section above for vendor advisories and patch information. Affected products include: Haxx Curl.