CVE-2026-54463Network attack vector

Process memory exhaustion via unbounded length parsing

Published Jul 17, 2026 · Updated Jul 17, 2026

Resource exhaustion in Faye websocket-driver before 0.8.1 allows remote attackers to exhaust process memory through draft WebSocket frames. The draft-75/76 parser repeatedly multiplies an arbitrary-precision Ruby length integer by 128 for high-bit-set bytes without enforcing its configured maximum. Either a server or client peer can trigger the condition on one WebSocket connection, causing the host process to run out of memory.

CVSS severity6.9
Medium
EPSS probability0.34%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Resource exhaustion in Faye websocket-driver before 0.8.1 allows remote attackers to exhaust process memory through draft WebSocket frames. The draft-75/76 parser repeatedly multiplies an arbitrary-precision Ruby length integer by 128 for high-bit-set bytes without enforcing its configured maximum. Either a server or client peer can trigger the condition on one WebSocket connection, causing the host process to run out of memory.

The record

CVE
CVE-2026-54463
Published
Jul 17, 2026
Updated
Jul 17, 2026
Vendor
Faye
Product
websocket-driver-ruby
Classifications
T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 17, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 17, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 0.8.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Faye · websocket-driver-rubyversion=< 0.8.1

Published CVSS scores

6.9GitHubCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Endpoint Denial of Service: Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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