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CVE-2021-42340

DoS via memory leak with WebSocket connections

HIGH
7.5
CVSS Score
Published: October 14, 2021 at 07:55 PM UTC
Updated: June 17, 2026 at 04:09 AM UTC
18 products affected across 4 vendorsDebian LinuxTomcatCommunications Diameter Signaling Router

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Severity
HIGH7.5
Exploit prediction
EPSS 12%

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Tomcat· Apache
95%
v ≤ 10.0.11v ≤ 10.1.0-M5v ≤ 8.5.71v ≤ 9.0.5310.0.1 ≤ v < 10.0.128.5.60 ≤ v < 8.5.729.0.40 ≤ v < 9.0.5410.0.0 milestone1010.1.0 milestone110.1.0 milestone210.1.0 milestone310.1.0 milestone410.1.0 milestone5
Affected range stops below 10.0.12, so it looks safe — our inference, not a vendor statement
Affected range stops below 8.5.72, so it looks safe — our inference, not a vendor statement
Affected range stops below 9.0.54, so it looks safe — our inference, not a vendor statement
Debian Linux· Debiandrupal
95%
11.0
Hci· NetApp
95%
All versions
Management Services for Element Software· NetApp
95%
All versions
Agile Engineering Data Management· Oracle
95%
6.2.1.0
Big Data Spatial and Graph· Oracledrupal
95%
v < 23.1
Affected range stops below 23.1, so it looks safe — our inference, not a vendor statement
Communications Diameter Signaling Router· Oracle
95%
8.0.0.0 ≤ v ≤ 8.5.0.2
Hospitality Cruise Shipboard Property Management System· Oracle
95%
20.1.0
Managed File Transfer· Oracle
95%
12.2.1.3.012.2.1.4.0
Middleware Common Libraries and Tools· Oracle
95%
12.2.1.4.0

References (9)

x_refsource_CONFIRMThird Party Advisory
Source: [email protected]
https://kc.mcafee.com/corporate/index?page=content&id=SB10379
Mailing Listx_refsource_MLIST
Source: [email protected]
https://lists.apache.org/thread.html/r8097a2d1550aa78e585fc77e602b9046e6d4099d8d132497c5387784%40%3Ccommits.myfaces.apache.org%3E
x_refsource_MISCMailing ListVendor Advisory
Source: [email protected]
https://lists.apache.org/thread.html/r83a35be60f06aca2065f188ee542b9099695d57ced2e70e0885f905c%40%3Cannounce.tomcat.apache.org%3E
Vendor Advisoryx_refsource_GENTOOThird Party Advisory
Source: [email protected]
https://security.gentoo.org/glsa/202208-34
x_refsource_CONFIRMThird Party Advisory
Source: [email protected]
https://security.netapp.com/advisory/ntap-20211104-0001/
Vendor Advisoryx_refsource_DEBIANThird Party Advisory
Source: [email protected]
https://www.debian.org/security/2021/dsa-5009
x_refsource_MISCPatchThird Party Advisory
Source: [email protected]
https://www.oracle.com/security-alerts/cpuapr2022.html
x_refsource_MISCPatchThird Party Advisory
Source: [email protected]
https://www.oracle.com/security-alerts/cpujan2022.html

CVSS

7.5HIGH[email protected]
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-772

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