Home/CVE/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
CVE

CVE-2021-41079

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

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.

HIGH · CVSS 7.5 EPSS 0.00103
Schedule remediation
  • CVSS base score ≥ 7.0
Sigma rules1 YARA rules0
⬡

Weakness Classification

CWE-20Improper Input Validation
CWE-835Loop with Unreachable Exit Condition ('Infinite Loop')
▤

Affected Products & Versions

5
apache tomcat>= 8.5.0 and < 8.5.64
apache tomcat>= 9.0.0 and < 9.0.44
apache tomcat>= 10.0.0 and <= 10.0.2
debian linuxall versions
netapp management services for element software and netapp hciall versions
▤

Affected Packages

1
Language-ecosystem packages (from OSV) tied to this CVE, with the version that fixes it - the dependency-level detail NVD doesn’t carry.
Maven org.apache.tomcat:tomcat HIGH fixed in 10.0.4
◈

Sigma Hunt Rules

1
Exact rules name this CVE ID. Product rules name an affected product in their title. Related rules cover techniques used by actors who exploited this CVE. Showing the most relevant matches; the complete related set is on the full drill-down.
productmediumTomcat WebServer Logs Deleted
▣

Scoring & Timeline

7.5
HIGH · CVSS v3.1 · security@apache.org
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD16 Sep 2021 · 03:15 PM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
⚑

Vendor Advisories

16
suse-csafSUSE-SU-2026:1058-1
usnUSN-6943-1
suse-csafopenSUSE-SU-2024:11618-1
suse-csafopenSUSE-SU-2024:13441-1
rhsaRHSA-2022:5532Important
🔗

References & Sources

6
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://lists.apache.org/thread.html/r6b6b674e3f168dd010e67dbe6848b866e2acf26371452fdae313b98a%40%3Cusers.tomcat.apache.org%3E
https://lists.apache.org/thread.html/rb4de81ac647043541a32881099aa6eb5a23f1b7fd116f713f8ab9dbe%40%3Cdev.tomcat.apache.org%3E
https://lists.apache.org/thread.html/rccdef0349fdf4fb73a4e4403095446d7fe6264e0a58e2df5c6799434%40%3Cannounce.tomcat.apache.org%3EMailing ListVendor Advisory
https://lists.debian.org/debian-lts-announce/2021/09/msg00012.htmlMailing ListThird Party Advisory
https://security.netapp.com/advisory/ntap-20211008-0005/Third Party Advisory
https://www.debian.org/security/2021/dsa-4986Third Party Advisory
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