SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAwaiting Analysis

CVE-2026-83599

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…

HIGH 7.5EPSS 0.74%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.74%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

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.

CVSS 3.1
7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS
0.74% probability · 54th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-409
Source
security-advisories@github.com
EPSS trend
0%3%5%23 September 2026: 0.74%26 October 2026: 0.74%23 September 202626 October 2026

EPSS moved from 0.7% on 23 September 2026 to 0.7% on 26 October 2026.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.