CVE-2026-54463: websocket-driver is a WebSocket protocol handler with pluggable I/O. Prior to 0.8.1, draft versions of the WebSocket protocol in websocket-driver include a length header that allow

unknownCVE-2026-54463

websocket-driver is a WebSocket protocol handler with pluggable I/O. Prior to 0.8.1, draft versions of the WebSocket protocol in websocket-driver include a length header that allows an arbitrarily large integer to be encoded as bytes with the high bit set, and a server or client can send an indefinite sequence of 0x80 or higher bytes that the peer parses into an ever-growing Ruby integer. This can make a WebSocket connection consume an unbounded amount of memory and lead to the host process running out of memory. This issue is fixed in version 0.8.1.

Details

Source: NVD Recent CVEs (US · database · site)
Severity: unknown
Published: 2026-07-17
Last updated: 2026-07-23
Exploitation: Not in CISA KEV at last sync

Original advisory: https://nvd.nist.gov/vuln/detail/CVE-2026-54463

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-544630.32% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 25% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-54463	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

mediumGHSA-ghhp-3qvg-889p: websocket-driver: Memory exhaustion via abuse of protocol length headersghsa

Recent advisories for websocket-driver is a

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

unknownCVE-2026-54490: websocket-driver is a WebSocket protocol handler with pluggable I/O. Prior to 0.7.5, if this l…nvd · 2026-07-17
unknownCVE-2026-54466: websocket-driver is a WebSocket protocol handler with pluggable I/O. Prior to 0.7.5, the frame…nvd · 2026-07-17
unknownCVE-2026-54465: websocket-driver is a WebSocket protocol handler with pluggable I/O. Prior to 0.8.1, when webs…nvd · 2026-07-17
mediumGHSA-mp7j-qc5w-4988: websocket-driver: Resource limit bypass via message compressionghsa · 2026-07-15
criticalGHSA-xv26-6w52-cph6: websocket-driver: Message corruption via abuse of protocol length headersghsa · 2026-07-15
mediumGHSA-8j3g-f24p-4mpw: websocket-driver: Memory exhaustion in HTTP header parserghsa · 2026-07-15