---
id: CVE-2026-83599
title: Netdata is an open source observability tool
summary: >-
  Netdata is an open source observability tool. Prior to 2.11.0, Netdata's
  unauthenticated WebSocket server negotiates permessage-deflate before
  authentication, and src/web/websocket/websocket-compression.c allows
  websocket_client_decompre…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-409
vendor: netdata
product: netdata
affected:
  - netdata < 2.11.0
published: '2026-09-22'
updated: '2026-09-23'
sourceUpdated: '2026-09-23T18:28:25.093'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-83599'
references:
  - url: >-
      https://github.com/netdata/netdata/commit/e3811f7ee6e9fdfc4cbcb9929cab3f5d71d722d7
    label: security-advisories@github.com
  - url: 'https://github.com/netdata/netdata/pull/22828'
    label: security-advisories@github.com
  - url: 'https://github.com/netdata/netdata/releases/tag/v2.11.0'
    label: security-advisories@github.com
  - url: 'https://github.com/netdata/netdata/security/advisories/GHSA-c8p4-cg3j-f4h2'
    label: security-advisories@github.com
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-83599.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-83599'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-83599'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
epss: 0.00742
epssPercentile: 0.52815
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-09-22T17:36:21.063916Z'
ingestedAt: '2026-09-22T17:07:07.378Z'
---

## Overview

Netdata is an open source observability tool. Prior to 2.11.0, Netdata's unauthenticated WebSocket server negotiates permessage-deflate before authentication, and src/web/websocket/websocket-compression.c allows websocket_client_decompress_message() to grow decompressed output toward WS_MAX_DECOMPRESSED_SIZE without enforcing a compressed-to-decompressed ratio. Small highly compressed frames can therefore cause large server-side allocations, and repeated concurrent connections can exhaust memory and terminate monitoring. This vulnerability is fixed in 2.11.0.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Vendor advisories

- **Red Hat VEX** · updated 2026-09-23 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-83599.json)