Resource exhaustion in Http4s Blaze

CVE-2026-73493

Http4s (http4s-blaze-server) is a minimal, idiomatic Scala interface for HTTP services. Prior to 0.23.18 and 1.0.0-M42, http4s-blaze-server aggregates fragments of an incoming WebSocket message with no limit on total size or fragment count…

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

  • Http4s Blaze — versions < 0.23.18, >= 1.0.0-M1, < 1.0.0-M42

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-73493?
CVE-2026-73493 is a high-severity vulnerability in Http4s Blaze, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 7.5/10. Published 2026-08-12.
How severe is CVE-2026-73493?
High severity. CVSS v3 base score is 7.5 out of 10.