Vulnerability · Published Jul 3, 2026 · Assigned by curl
CVE-2026-11352QUIC zero-length UDP datagrams busy-loop
High 7.5
In plain English
A high-severity infinite loop in curl from curl. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 1.0% (higher than 63% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.23 | curl | 8.22.0-r0 | ALPINE-CVE-2026-11352 |
| Alpine:v3.24 | curl | 8.21.0-r0 | ALPINE-CVE-2026-11352 |
| Debian:14 | curl | 8.21.0~rc2-1 | DEBIAN-CVE-2026-11352 |
| Ubuntu:26.04:LTS | curl | 8.18.0-1ubuntu2.3 | UBUNTU-CVE-2026-11352 |
Affected products (as reported)
Weakness: CWE-835 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H