CVE-2026-69213 (GCVE-0-2026-69213)

Vulnerability from cvelistv5 – Published: 2026-09-15 19:08 – Updated: 2026-09-17 16:43
VLAI
Title
Http4s Ember HTTP/2: unbounded outbound frame queue
Summary
Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, Ember HTTP/2 serializes outbound frames through one unbounded queue consumed by writeLoop. When the peer stops reading, an unauthenticated HTTP/2 client can continue sending PING, SETTINGS, or DATA frames that cause Ember to enqueue acknowledgments or WINDOW_UPDATE frames faster than the writer drains them, exhausting heap memory on a server built with withHttp2. The shared behavior also affects an ember-client connected to a hostile HTTP/2 server, and the patch replaces the unbounded path with bounded, backpressured outbound queues. This issue is fixed in versions 0.23.35 and 1.0.0-M47.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-17 16:42 UTC
CWE
  • CWE-400 - Uncontrolled Resource Consumption
  • CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7609 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
http4s http4s Affected: < 0.23.35
Affected: >= 1.0.0-M1, < 1.0.0-M47
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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