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Fencer Intel
high 7.5

CVE-2020-7662 json

Regular Expression Denial of Service in websocket-extensions (NPM package)

published 6y ago modified 4mo ago also GHSA-g78m-2chm-r7qv , EUVD-2020-0489

cvss
7.5
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
3.1%
EPSS 3.1% chance of exploitation in 30 days, percentile 87%
public exploits
0
none known

Summary

websocket-extensions npm module prior to 0.1.4 allows Denial of Service (DoS) via Regex Backtracking. The extension parser may take quadratic time when parsing a header containing an unclosed string parameter value whose content is a repeating two-byte sequence of a backslash and some other character. This could be abused by an attacker to conduct Regex Denial Of Service (ReDoS) on a single-threaded server by providing a malicious payload with the Sec-WebSocket-Extensions header.

Patch / fix

  • npm websocket-extensions 0.1.4
  • websocket-extensions_project websocket-extensions 0.1.4
  • servicemesh-grafana service mesh 1.0 6.2.2-38.el8
  • servicemesh-grafana-prometheus service mesh 1.0 6.2.2-38.el8
  • servicemesh-grafana service mesh 1.1 6.4.3-11.el8
  • servicemesh-grafana-prometheus service mesh 1.1 6.4.3-11.el8

red hat advisories RHSA-2020:2861RHSA-2020:2796

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2020-7662 updated cvss 7.5

npmjs-websocket-extensions: ReDoS vulnerability in Sec-WebSocket-Extensions parser

  • Red Hat OpenShift Container Platform 4 openshift4/ose-prometheus
    affected: no fix available “Fix deferred”
  • Red Hat OpenShift Service Mesh 1.0 servicemesh-grafana 6.2.2-38.el8, servicemesh-grafana-prometheus 6.2.2-38.el8
    fixed: vendor fix RHSA-2020:2861
  • Red Hat OpenShift Service Mesh 1.1 servicemesh-grafana 6.4.3-11.el8, servicemesh-grafana-prometheus 6.4.3-11.el8
    fixed: vendor fix RHSA-2020:2796
  • Red Hat OpenShift Container Platform 4.6 openshift4/ose-grafana v4.6.0-202010061132.p0
    fixed: vendor fix RHSA-2020:4298
  • Red Hat OpenShift Container Platform 4.6 openshift4/ose-cli v4.6.0-202010080605.p0, openshift4/ose-ptp v4.6.0-202010200139.p0, openshift4/ose-etcd v4.6.0-202010061132.p0, openshift4/ose-tests v4.6.0-202010120952.p0, openshift4/ose-console v4.6.0-202010100121.p0, openshift4/ose-coredns v4.6.0-202010061132.p0, +79 more
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

3.09% chance of exploitation in the next 30 days, higher than 87% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • blog.jcoglan.com https://blog.jcoglan.com/2020/06/02/redos-vulnerability-in-websocket-extensions referenced PoC, tagged "exploit" by a source, unverified
  • github.com https://github.com/faye/websocket-extensions-node/security/advisories/GHSA-g78m-2chm-r7qv referenced PoC, tagged "exploit" by a source, unverified
  • snyk.io https://snyk.io/vuln/SNYK-JS-WEBSOCKETEXTENSIONS-570623 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD 2.0 5.0 AV:N/AC:L/Au:N/C:N/I:N/A:P
GitHub 3.1 8.2 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H

Affected packages

ecosystem package affected fixed in
npm websocket-extensions
<0.1.4
0.1.4

Affected products

  • n/a websocket-extensions (npm)

Classification

Weakness
  • CWE-400 Uncontrolled Resource Consumption

References

Sources

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