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 Details
- CVSS 3.1 Base Score: 7.5
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alpine Linux | — | Upgrade curl | Jul 6, 2026 | Jul 3, 2026 |
| Redhat_linux | — | — | Jul 17, 2026 | Jul 3, 2026 |
| Ubuntu | — | Upgrade libcurl3t64-gnutlsUpgrade libcurl4-gnutls-devUpgrade libcurl4-openssl-devUpgrade libcurl4t64Upgrade curl | Jul 12, 2026 | Jul 9, 2026 |
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