High severity · published Sep 16, 2021
CVE-2021-41079
Apache Tomcat DoS with unexpected TLS packet
7.5
CVSS
7.2%
EPSS
No
On KEV
Description
Apache Tomcat 8.5.0 to 8.5.63, 9.0.0-M1 to 9.0.43 and 10.0.0-M1 to 10.0.2 did not properly validate incoming TLS packets. When Tomcat was configured to use NIO+OpenSSL or NIO2+OpenSSL for TLS, a specially crafted packet could be used to trigger an infinite loop resulting in a denial of service.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)7.2% · higher than 94% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
TO
Tomcat · Apache
Apache Tomcat 8.5 8.5.0 to 8.5.63; Apache Tomcat 9 9.0.0-M1 to 9.0.43; Apache Tomcat 10 10.0.0-M1 to 10.0.2 · source: vendor, NVD
DL
Debian Linux · Debian
9.0; 10.0; 11.0 · source: NVD
MS
Management Services For Element Software And Netapp Hci · Netapp
All versions, or not specified · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-41079
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-41079
lists.apache.org
https://lists.apache.org/thread.html/r6b6b674e3f168dd010e67dbe6848b866e2acf26371452fdae313b98a%40%3Cusers.tomcat.apache.org%3E
lists.apache.org
https://lists.apache.org/thread.html/rb4de81ac647043541a32881099aa6eb5a23f1b7fd116f713f8ab9dbe%40%3Cdev.tomcat.apache.org%3E
Mailing List
https://lists.apache.org/thread.html/rccdef0349fdf4fb73a4e4403095446d7fe6264e0a58e2df5c6799434%40%3Cannounce.tomcat.apache.org%3E
Mailing List
https://lists.debian.org/debian-lts-announce/2021/09/msg00012.html
Third Party Advisory
https://security.netapp.com/advisory/ntap-20211008-0005/
Third Party Advisory
https://www.debian.org/security/2021/dsa-4986
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