CVE-2020-7662

mediumpriority · track · 31EPSS 0.031 · 88 %ileDEEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

3.09% (88th) EPSS

CVSS 5 · medium

Is it mine?

22 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · osv · cert_bund

EPSS · scored 2026-10-27

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.

cvss

Technical severity, 0–10. One row per scoring source.

8.2

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–8.2

v2.05mediumAV:N/AC:L/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.18.2highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:Hsecondary · OSV

v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-400US

affected products (22)

Products and version ranges known to be affected.

Atlassian Confluence <10.0.2all versionscert_bundDE
Atlassian Confluence <10.1.1all versionscert_bundDE
Atlassian Confluence <8.5.25all versionscert_bundDE
Atlassian Confluence <9.2.7all versionscert_bundDE
Dell Data Protection Advisor <19.12all versionscert_bundDE
IBM DB2all versionscert_bundDEcpe:/a:ibm:db2:-
Red Hat Enterprise Linuxall versionscert_bundDEcpe:/o:redhat:enterprise_linux:-
SUSE Linuxall versionscert_bundDEcpe:/o:suse:suse_linux:-
Splunk Splunk Enterprise <8.1.14all versionscert_bundDE
Splunk Splunk Enterprise <8.2.11all versionscert_bundDE
Splunk Splunk Enterprise <9.0.5all versionscert_bundDE
Atlassian Confluence< 10.0.2cert_bundDE
Atlassian Confluence< 10.1.1cert_bundDE
Atlassian Confluence< 8.5.25cert_bundDE
Atlassian Confluence< 9.2.7cert_bundDE
Dell Data Protection Advisor< 19.12cert_bundDE
Splunk Splunk Enterprise< 8.1.14cert_bundDE
Splunk Splunk Enterprise< 8.2.11cert_bundDE
Splunk Splunk Enterprise< 9.0.5cert_bundDE
n/a websocket-extensions (npm)≤ All versions prior to 0.1.4enisa_euvdEU

showing 20 of 22

advisories (3)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2023-1350Splunk Splunk Enterprise: Mehrere Schwachstellen in Komponenten von DrittanbieternDeutsch2023-06-01csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Splunk Splunk Enterprise in diversen Komponenten von Drittanbietern ausnutzen, um einen nicht näher spezifizierten Angriff durchzuführen.
WID-SEC-W-2026-0777Red Hat OpenShift: Mehrere SchwachstellenDeutsch2020-07-01csaf · cert_bundDE
Ein entfernter, authentisierter Angreifer kann mehrere Schwachstellen in Red Hat OpenShift ausnutzen, um einen Denial of Service Angriff durchzuführen, einen Cross-Site-Scripting-Angriff durchzuführen, beliebigen Programmcode auszuführen, oder Auswirkungen hinsichtlich der Vertraulichkeit, Verfügbarkeit und Integrität zu verursachen.
GHSA-g78m-2chm-r7qvRegular Expression Denial of Service in websocket-extensions (NPM package)2020-06-05ghsa · osvUS
### 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/

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd osv cert_bund NVD CVE.org MITRE

published 2020-06-02modified 2026-06-17

references (21)

External citations — patches, advisories, analysis.

scry

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