EUVD-2026-79192Vulnerability Assessment
| Weakness |
CWE
ASVS 5.0
V15 - Secure Coding and Architecture Loop termination conditions
MITRE ATT&CK
1 technique across 1 tactic: Impact The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
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Alert meAnalysisAIv1 – Sep 15, 2026
A crafted WebSocket frame can pin a worker thread and exhaust memory in the http4s Scala HTTP library, causing denial of service on servers built with the Ember backend. The flaw lies in WebSocket FrameTranscoder.bodyLength, which rejects extended payload lengths above Integer.MAX_VALUE but accepts negative 64-bit lengths; a remote client that completes a WebSocket handshake can send such a frame, and the decoder then returns an empty frame without advancing its input, so the decode loop spins forever while an ArrayBuffer grows without bound. Versions prior to 0.23.35 and 1.0.0-M47 are affected, and both fix releases are available; no public exploit tooling was identified at time of analysis, though the trigger frame is easily reconstructed from the public regression test added in the fix commit.
Affected VersionsENISA
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 2 packages in euvd
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Primary rating from Vendor (GitHub_M) · only source for this CVE.
CVSS VectorVendor: GitHub_M
Lifecycle Timeline
2DescriptionCVE.org
Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, WebSocket FrameTranscoder.bodyLength rejects extended payload lengths above Integer.MAX_VALUE but permits negative 64-bit lengths. A remote client that completes a WebSocket handshake through an Ember server can send such a frame, causing the decoder to return an empty frame without advancing its input. The decode loop then runs indefinitely, pins a worker at full CPU, and grows an ArrayBuffer without bound, resulting in denial of service. This issue is fixed in versions 0.23.35 and 1.0.0-M47.
Technical POC Analysis
CWE-835 (Loop with Unreachable Exit Condition), with CWE-1284 (Improper Validation of Specified Quantity in Input) as the underlying validation defect.
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Threat Intelligence Overview
NVD
CVE.org
EPSS
GitHub
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.
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