CVE-2021-42340

mediumpriority · track · 34EPSS 0.118 · 96 %ileDEEURUUS

grimoire priorityP1 · Urgent

Exploitable?

—

no known exploitation

Likely / severe?

11.8% (96th) EPSS

CVSS 5 · medium

Is it mine?

99 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · osv

EPSS · scored 2026-10-27

The fix for bug 63362 present in Apache Tomcat 10.1.0-M1 to 10.1.0-M5, 10.0.0-M1 to 10.0.11, 9.0.40 to 9.0.53 and 8.5.60 to 8.5.71 introduced a memory leak. The object introduced to collect metrics for HTTP upgrade connections was not released for WebSocket connections once the connection was closed. This created a memory leak that, over time, could lead to a denial of service via an OutOfMemoryError.

cvss

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

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5

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

v3.17.5highAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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-772USprimaryCWE-772USCWE-772US

affected products (99)

Products and version ranges known to be affected.

Atlassian Bitbucket <10.0.2all versionscert_bundDE
Atlassian Bitbucket <8.19.25 (LTS)all versionscert_bundDE
Atlassian Bitbucket <9.4.13 (LTS)all versionscert_bundDE
Debian Linuxall versionscert_bundDEcpe:/o:debian:debian_linux:-
EMC Avamarall versionscert_bundDEcpe:/a:emc:avamar:-
Hitachi Ops Centerall versionscert_bundDEcpe:/a:hitachi:ops_center:-
IBM Operational Decision Managerall versionscert_bundDEcpe:/a:ibm:operational_decision_manager:-
IBM QRadar SIEMall versionscert_bundDEcpe:/a:ibm:qradar_siem:-
IBM QRadar SIEM 7.4all versionscert_bundDEcpe:/a:ibm:qradar_siem:7.4
IBM QRadar SIEM 7.5all versionscert_bundDEcpe:/a:ibm:qradar_siem:7.5
IBM Spectrum Protect plus 10.1all versionscert_bundDEcpe:/a:ibm:spectrum_protect:plus_10.1
NetApp ActiveIQ Unified Managerall versionscert_bundDEcpe:/a:netapp:active_iq_unified_manager:-::~~~vmware_vsphere~~
Red Hat Enterprise Linuxall versionscert_bundDEcpe:/o:redhat:enterprise_linux:-
Red Hat FUSE <7.11.0all versionscert_bundDE
Red Hat JBoss Enterprise Application Platform <7.1.10all versionscert_bundDE
Red Hat JBoss Enterprise Application Platform <7.3.13all versionscert_bundDE
Atlassian Bitbucket< 10.0.2cert_bundDE
Atlassian Bitbucket< 8.19.25 (LTS)cert_bundDE
Atlassian Bitbucket< 9.4.13 (LTS)cert_bundDE
Red Hat Fuse< 7.11.0cert_bundDE

showing 20 of 99

advisories (7)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2022-0169Oracle MySQL: Mehrere SchwachstellenDeutsch2022-04-19csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Oracle MySQL ausnutzen, um die Vertraulichkeit, Integrität und Verfügbarkeit zu gefährden.
WID-SEC-W-2022-0607Red Hat FUSE: Mehrere SchwachstellenDeutsch2022-07-07csaf · cert_bundDE
Ein entfernter, anonymer, authentisierter oder lokaler Angreifer kann mehrere Schwachstellen in Red Hat FUSE ausnutzen, um vertrauliche Informationen offenzulegen, beliebigen Code auszuführen, einen Denial of Service Zustand herbeizuführen, Sicherheitsmaßnahmen zu umgehen, Daten und Informationen zu manipulieren und seine Privilegien zu erweitern.
WID-SEC-W-2022-1121Apache Tomcat: Schwachstelle ermöglicht Denial of ServiceDeutsch2021-10-14csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann eine Schwachstelle in Apache Tomcat ausnutzen, um einen Denial of Service Angriff durchzuführen.
WID-SEC-W-2022-1375JFrog Artifactory: Mehrere SchwachstellenDeutsch2022-09-11csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in JFrog Artifactory ausnutzen, um seine Privilegien zu erweitern, beliebigen Code auszuführen, Sicherheitsmaßnahmen zu umgehen, vertrauliche Informationen offenzulegen und einen Denial-of-Service-Zustand auszulösen.
WID-SEC-W-2024-1238HPE HP-UX: Mehrere SchwachstellenDeutsch2024-05-27csaf · cert_bundDE
Ein anonymer oder lokaler Angreifer kann mehrere Schwachstellen in HPE HP-UX Tomcat Servlet Engine ausnutzen, um Sicherheitsmaßnahmen zu umgehen, einen Denial-of-Service-Zustand zu verursachen, vertrauliche Informationen offenzulegen oder Dateien zu manipulieren.
GHSA-wph7-x527-w3h5Missing Release of Resource after Effective Lifetime in Apache Tomcat2021-10-15ghsa · osvUS
The fix for bug 63362 present in Apache Tomcat 10.1.0-M1 to 10.1.0-M5, 10.0.0-M1 to 10.0.11, 9.0.40 to 9.0.53 and 8.5.60 to 8.5.71 introduced a memory leak. The object introduced to collect metrics for HTTP upgrade connections was not released for WebSocket connections once the connection was closed. This created a memory leak that, over time, could lead to a denial of service via an OutOfMemoryError.
BIT-tomcat-2021-42340DoS via memory leak with WebSocket connections2024-03-06vendor · osvUS
The fix for bug 63362 present in Apache Tomcat 10.1.0 to 10.1.0, 10.0.0 to 10.0.11, 9.0.40 to 9.0.53 and 8.5.60 to 8.5.71 introduced a memory leak. The object introduced to collect metrics for HTTP upgrade connections was not released for WebSocket connections once the connection was closed. This created a memory leak that, over time, could lead to a denial of service via an OutOfMemoryError.

also known as (6)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu osv cert_bund NVD CVE.org MITRE

published 2021-10-14modified 2026-06-17

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+1024 more

references (49)

External citations — patches, advisories, analysis.

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