GitHub Advisoryadvisory · npm

GHSA-g78m-2chm-r7qv Regular Expression Denial of Service in websocket-extensions (NPM package)

HIGH Published 2020-06-05 Modified 2021-08-25 Official page ↗
Aliases
CVE-2020-7662
Ecosystem
npm
Packages
websocket-extensions
Severity
High
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
Weaknesses
CWE-400
Reviewed
2020-06-03

Affected packages

• npm websocket-extensions: < 0.1.4 → fixed in 0.1.4

Description

Impact The ReDoS flaw allows an attacker to exhaust the server's capacity to process incoming requests by sending a WebSocket handshake request containing a header of the following form: Sec-WebSocket-Extensions: a; b="\c\c\c\c\c\c\c\c\c\c ... That is, a header containing an unclosed string parameter value whose content is a repeating two-byte sequence of a backslash and some other character. The parser takes exponential time to reject this header as invalid, and this will block the processing of any other work on the same thread. Thus if you are running a single-threaded server, such a request can render your service completely unavailable. Patches Users should upgrade to version 0.1.4. Workarounds There are no known work-arounds other than disabling any public-facing WebSocket functionality you are operating. References • https://blog.jcoglan.com/2020/06/02/redos-vulnerability-in-websocket-extensions/

Related

Alias · CVE (1)

  • CVE-2020-7662 websocket-extensions npm module prior to 0.1.4 allows Denial of Service (DoS) via Regex Backtracking. vulnerability

Weakness · CWE (1)

  • CWE-400 Uncontrolled Resource Consumption weakness

References