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CVE-2021-32640

ReDoS in Sec-Websocket-Protocol header

Published: May 25, 2021Updated: Nov 21, 2024 Sources: CVE List NVD GHSA BDUCWE-400
NVD MITRE
5.3CVSSMEDIUM
EPSS Score
2.9%
Top 14.7%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

Description

ws is an open source WebSocket client and server library for Node.js. A specially crafted value of the `Sec-Websocket-Protocol` header can be used to significantly slow down a ws server. The vulnerability has been fixed in ws@7.4.6 (https://github.com/websockets/ws/commit/00c425ec77993773d823f018f64a5c44e17023ff). In vulnerable versions of ws, the issue can be mitigated by reducing the maximum allowed length of the request headers using the [`--max-http-header-size=size`](https://nodejs.org/api/cli.html#cli_max_http_header_size_size) and/or the [`maxHeaderSize`](https://nodejs.org/api/http.html#http_http_createserver_options_requestlistener) options.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:NI:NA:L
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:LAvailability
Low
Open in CVSS calculator →

Weaknesses

CWE-400

Affected Products

wsws project
Library
OSS Libraries / npm
e-series performance analyzernetappHardware Firmware
wsnpmOSS Libraries
wswebsockets
Mixed
Web & CMS Plugins / cms-core
Debian GNU/LinuxСообщество свободного программного обеспечения
On-premOS
Operating Systems / linux-distro
ws projectpackage-ecosystemOSS Librariesaka ws
netappcommercialUSHardware Firmware
npmpackage-ecosystemOSS Libraries
websocketscommercialWeb & CMS Pluginsaka websockets
сообщество свободного программного обеспеченияoss-projectOperating Systemsaka сообщество свободного программного обеспечения, fsf
and 1 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

Official Patch Available
Workaround Available

MITRE ATT&CK

1 technique
Impact
View detailed technique mapping

References

https://github.com/websockets/ws/commit/00c425ec77993773d823f018f64a5c44e17023ff
github.com
https://github.com/websockets/ws/security/advisories/GHSA-6fc8-4gx4-v693
github.com
https://lists.apache.org/thread.html/rdfa7b6253c4d6271e31566ecd5f30b7ce1b8fb2c89d52b8c4e0f4e30%40%3Ccommits.tinkerpop.apache.org%3E
lists.apache.org
and 10 more references View all →

Timeline

Published
May 25, 2021
Last Updated
Nov 21, 2024

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