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Low severity · published Sep 28, 2022
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)…
3.7
CVSS
2.4%
EPSS
No
On KEV
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 vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.4% · higher than 84% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
TO
Tomcat · Apache
8.5.0 through 8.5.77; 9.0.0 through 9.0.60; 10.0.0 through 10.0.18; 10.1.0; 10.1.0; 10.1.0; +9 more · source: NVD
DL
Debian Linux · Debian
10.0; 11.0 · source: NVD
Affected product
TO
Tomcat
Apache
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-43980
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-43980
Mailing List
http://www.openwall.com/lists/oss-security/2022/09/28/1
Mailing List
https://lists.apache.org/thread/3jjqbsp6j88b198x5rmg99b1qr8ht3g3
Mailing List
https://lists.debian.org/debian-lts-announce/2022/10/msg00029.html
Third Party Advisory
https://www.debian.org/security/2022/dsa-5265
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