CVE-2026-66299

mediumpriority · track · 21EPSS 0.006 · 46 %ileDEEUFRNLRUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.55% (46th) EPSS

CVSS 5.3 · medium

Is it mine?

50 products

Check your exposure

Who says so?

7 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

Uncontrolled Resource Consumption vulnerability in Apache Tomcat's WebSocket chat example. This issue affects Apache Tomcat: from 11.0.0-M20 through 11.0.24, from 10.1.24 through 10.1.57, from 9.0.89 through 9.0.120. Users who have followed the security guidance to remove the examples web application are not affected by this issue. Users are recommended to remove the examples web application or to upgrade to version 11.0.25, 10.1.58 or 9.0.121 (when released), which fix the issue.

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 · 4.9–7.5

v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Lprimary · NVD / NIST USexploitability 3.9 · impact 1.4

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 · ENISA EU

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

v3.14.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:Usecondary · CVSS-BT (t0sche)

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · NCSC-NL NL

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-400USCWE-400USCWE-770US

affected products (50)

Products and version ranges known to be affected.

Amazon Linux 2all versionscert_bundDEcpe:/o:amazon:linux_2:-
Red Hat Enterprise Linuxall versionscert_bundDEcpe:/o:redhat:enterprise_linux:-
SUSE Linuxall versionscert_bundDEcpe:/o:suse:suse_linux:-
SUSE openSUSEall versionscert_bundDEcpe:/o:suse:opensuse:-
Apache Tomcat< 10.1.58cert_bundDE
Apache Tomcat< 11.0.25cert_bundDE
Apache Tomcat< 9.0.121cert_bundDE
Apache Software Foundation Apache Tomcat≤ 10.1.24 ≤10.1.57enisa_euvdEU
Apache Software Foundation Apache Tomcat≤ 9.0.89 ≤9.0.120enisa_euvdEU
Apache Software Foundation Apache Tomcat≤ 11.0.0-M20 ≤11.0.24enisa_euvdEU
Apache Software Foundation Tomcat≤ 11.0.0-M21fstec_bduRU
Apache Software Foundation Tomcat≤ 11.0.0-M23fstec_bduRU
Apache Software Foundation Tomcat≤ 11.0.0-M22fstec_bduRU
Apache Software Foundation Tomcat≤ 11.0.0-M20fstec_bduRU
Apache Software Foundation Tomcat≤ 11.0.0-M26fstec_bduRU
Apache Software Foundation Tomcat≤ 11.0.0-M25fstec_bduRU
Apache Software Foundation Tomcat≤ 11.0.0-M24fstec_bduRU
Apache Software Foundation Tomcat10.1.24 → 10.1.58fstec_bduRU
Apache Software Foundation Tomcat11.0.1 → 11.0.25fstec_bduRU
Apache Software Foundation Tomcat9.0.89 → 9.0.121fstec_bduRU

showing 20 of 50

advisories (5)

Vendor and ecosystem advisories describing this.

NCSC-2026-0375Kwetsbaarheden verholpen in Oracle CommunicationsNL2026-09-16csaf · ncsc_nlNL
Oracle heeft 31 kwetsbaarheden verholpen in diverse Oracle Communications-producten, waaronder Oracle Communications Unified Assurance, Oracle Communications Cloud Native Core Security Edge Protection Proxy, Oracle Communications MetaSolv Solution Module - ASR, Oracle Communications Service Catalog and Design en Oracle Communications Operations Monitor.
WID-SEC-W-2026-2571Apache Tomcat: Schwachstelle ermöglicht Denial of ServiceDeutsch2026-07-28csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann eine Schwachstelle in Apache Tomcat ausnutzen, um einen Denial of Service Angriff durchzuführen.
WID-SEC-W-2026-3403Oracle Communications: Mehrere SchwachstellenDeutsch2026-09-15csaf · cert_bundDE
Ein entfernter, anonymer oder authentisierter Angreifer kann mehrere Schwachstellen in Oracle Communications ausnutzen, um die Vertraulichkeit, Integrität und Verfügbarkeit zu gefährden.
BIT-tomcat-2026-66299Apache Tomcat: DoS via WebSocket chat example2026-08-17vendor · osvUS
Uncontrolled Resource Consumption vulnerability in Apache Tomcat's WebSocket chat example. This issue affects Apache Tomcat: from 11.0.0 through 11.0.24, from 10.1.24 through 10.1.57, from 9.0.89 through 9.0.120. Users who have followed the security guidance to remove the examples web application are not affected by this issue. Users are recommended to remove the examples web application or to upgrade to version 11.0.25, 10.1.58 or 9.0.121 (when released), which fix the issue.
CERTFR-2026-AVI-1385Multiples vulnérabilités dans les produits VMwareFrançais2026-10-26vendor · certfrFR

also known as (5)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cert_bund ncsc_nl osv certfr NVD CVE.org MITRE

published 2026-07-28modified 2026-10-24

references (4)

External citations — patches, advisories, analysis.

https://lists.apache.org/thread/8owczcc1o8qw1rxmg9gvfk4w2jnh4l5k cnnvd
https://lists.apache.org/thread/8owczcc1o8qw1rxmg9gvfk4w2jnh4l5k enisa_euvd
http://www.openwall.com/lists/oss-security/2026/07/28/25Mailing ListThird Party Advisorynvd
https://lists.apache.org/thread/8owczcc1o8qw1rxmg9gvfk4w2jnh4l5kMailing ListVendor Advisorynvd

scry

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