QUIC zero-length UDP datagrams busy-loop (curl curl)
At a glance
- Source
- NVD
- EPSS
- EPSS 1.01 % · percentile 63 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- curl
- NVD status
- Modified
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.
Weaknesses (CWE)
- CWE-835 — Loop with Unreachable Exit Condition
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | CISA-ADP |
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | NVD · 134c704f-9b21-4f2e-91b3-4a467353bcc0 (Secondary) |
European references
- ENISA EUVD · EUVD-2026-41498
- GCVE · GCVE-0-2026-11352
CERT-FR advisories
- CERTFR-2026-AVI-1390 — Multiples vulnérabilités dans Tenable Network Monitor · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1385 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0797 — Multiples vulnérabilités dans cURL et libcurl · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:a:haxx:curl:*:*:*:*:*:*:*:*≥ 8.18.0 < 8.21.0
Affected products
| Product | Versions |
|---|---|
| curl · curl | affected 8.18.0 < 8.20.1 |
| curl · curl | affected 6a3d0b6d631d5e9bec797306b5b41a9f440a088d < 56eca2afb4806f1032872fa97d1834b3c1385276 |
| curl · curl | affected 8.20.0 ; affected 8.19.0 ; affected 8.18.0 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |