websocket-driver: Message corruption via abuse of protocol length headers (CVE-2026-54466) | HOL Guard CVE

Critical · CVSS 9.2CVE-2026-54466GHSA-XV26-6W52-CPH6

websocket-driver: Message corruption via abuse of protocol length headers

Answer in brief

CVE-2026-54466 records a Critical severity (CVSS 9.2) vulnerability in websocket-driver: Message corruption via abuse of protocol length headers. The current sources do not mark it as known exploited. The current feed maps websocket-driver (npm), websocket-driver (npm). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Jul 15, 2026Updated Sep 10, 2026Source checked Sep 17, 2026First seen by HOL Jul 15, 2026Material review Sep 10, 2026

Upstream Advisory

Key facts

Risk: Critical · CVSS 9.2
Exploitation: Not marked as known exploited
Affected software: 3 mapped packages or products
Fix availability: Available

Why this deserves its current priority

CVSS is 9.2. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps websocket-driver (npm), websocket-driver (npm). Check affected ranges and fixed versions before updating.

Affected products and reported versions
Product	Affected versions	Fixed versions
cpe:2.3:a:faye:websocket-driver::::::ruby::*	Not reported	Not reported

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
websocket-drivernpm	<0.7.5	0.7.5
websocket-drivernpm	>=0 <0.7.5	0.7.5

Recommended response

Check inventory. Check lockfiles and deployed manifests for websocket-driver, websocket-driver.
Review the reported fix. Update websocket-driver to 0.7.5; websocket-driver to 0.7.5 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Jul 15, 2026
Evidence: source:nvd:source_dates:source-dates:record
Source modified
Sep 10, 2026
Evidence: source:nvd:source_dates:source-dates:record
First seen by HOL
Jul 15, 2026

Sources and claim methodology

Upstream source description

### Impact The frame format in draft versions of the WebSocket protocol includes a length header that allows an arbitrarily large integer to be encoded as a sequence of bytes with the high bit set. By sending an indefinite sequence of bytes with values `0x80` or above, a client can make the server parse these bytes into an ever-growing integer. Since JavaScript numbers are 64-bit floating point values, this number will eventually lose precision and lead to the subsequent payload being parsed incorrectly. ### Patches The issue has been patched in version 0.7.5 by rejecting the message if the length header exceeds the configured maximum message length. All users should upgrade to this version. ### Workarounds No known workarounds exist. ### Acknowledgements This issue was discovered and reported by Pranjali Thakur, DepthFirst Security Research Team.

Quoted source text, attributed separately from HOL analysis.