SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2021-43980

The simplified implementation of blocking reads and writes introduced in Tomcat 10 and back-ported to Tomcat 9.0.47 onwards exposed a long standing (but extremely hard to trigger) concurrency bug in Apache Tomcat 10.1.0 to 10.1.0-M12, 10.0.0-M1 to…

LOW 3.7EPSS 1.89%

Does this matter?

Lower severity and a low EPSS score (1.89%). Track it; it rarely justifies an emergency change on its own.

Description

The simplified implementation of blocking reads and writes introduced in Tomcat 10 and back-ported to Tomcat 9.0.47 onwards exposed a long standing (but extremely hard to trigger) concurrency bug in Apache Tomcat 10.1.0 to 10.1.0-M12, 10.0.0-M1 to 10.0.18, 9.0.0-M1 to 9.0.60 and 8.5.0 to 8.5.77 that could cause client connections to share an Http11Processor instance resulting in responses, or part responses, to be received by the wrong client.

CVSS 3.1
3.7 LOWCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
EPSS
1.89% probability · 78th percentile
CISA KEV
Not listed
Weakness
CWE-362
Affected
apache/tomcat · debian/debian linux
Source
security@apache.org

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.