CVE-2026-11352

QUIC zero-length UDP datagrams busy-loop

cve-program · severity unknownCVSS unknownCheck source for fixed versionsKEV status unknown

Original advisory

cve-program · CVE-2026-11352

Published

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.

Read the publisher's advisory

Affected versions, risk and source history

cve-program · CVE-2026-11352

Published

curl

Vendor product

Publisher's version information

Shown as published. These rules are not interpreted as NuGet package version ranges.

{
                    "vendor": "curl",
                    "product": "curl",
                    "versions": [
                        {
                            "version": "8.18.0",
                            "status": "affected",
                            "versionType": "semver",
                            "lessThan": "8.20.1"
                        }
                    ],
                    "defaultStatus": "unaffected"
                }

curl

Vendor product

Publisher's version information

Shown as published. These rules are not interpreted as NuGet package version ranges.

{
                    "vendor": "curl",
                    "product": "curl",
                    "versions": [
                        {
                            "version": "6a3d0b6d631d5e9bec797306b5b41a9f440a088d",
                            "status": "affected",
                            "versionType": "git",
                            "lessThan": "56eca2afb4806f1032872fa97d1834b3c1385276"
                        }
                    ],
                    "defaultStatus": "unaffected",
                    "repo": "https://github.com/curl/curl.git"
                }

curl

Vendor product

Publisher's version information

Shown as published. These rules are not interpreted as NuGet package version ranges.

{
                    "vendor": "curl",
                    "product": "curl",
                    "versions": [
                        {
                            "version": "8.20.0",
                            "status": "affected"
                        },
                        {
                            "version": "8.19.0",
                            "status": "affected"
                        },
                        {
                            "version": "8.18.0",
                            "status": "affected"
                        }
                    ],
                    "defaultStatus": "unaffected"
                }

Original source record · Cite this exact observation · Complete original publisher JSON