CVE-2026-83599Network attack vectorHinoki check available

Unauthenticated service termination via WebSocket decompression bomb

Published Sep 22, 2026 · Updated Sep 22, 2026

CWE-409 in Netdata Agent before 2.11.0 allows remote attackers to terminate monitoring with compressed WebSocket frames. The unauthenticated server negotiates permessage-deflate before authentication, while websocket_client_decompress_message() grows output toward 200 MB without an expansion-ratio limit. Repeated concurrent connections can exhaust server memory, so exposure requires network access to the Agent's WebSocket listener.

CVSS severityUnavailable
Unscored
EPSS probability0.74%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

CWE-409 in Netdata Agent before 2.11.0 allows remote attackers to terminate monitoring with compressed WebSocket frames. The unauthenticated server negotiates permessage-deflate before authentication, while websocket_client_decompress_message() grows output toward 200 MB without an expansion-ratio limit. Repeated concurrent connections can exhaust server memory, so exposure requires network access to the Agent's WebSocket listener.

The record

CVE
CVE-2026-83599
Published
Sep 22, 2026
Updated
Sep 22, 2026
Vendor
Netdata
Product
Netdata Agent
Classifications
CWE-409, T1499.003
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 22, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 22, 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=< 2.11.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Netdata · Netdata Agentversion=< 2.11.0

Published CVSS scores

No CVSS assessment is available in this record.

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.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-409Improper Handling of Highly Compressed Data (Data Amplification)
T1499.003Application Exhaustion Flood

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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