Vulnerability-Lookup

Vulnerability from bitnami_vulndb

Published

2024-03-06 11:09

Modified

2026-09-08 08:34

Summary

Apache Tomcat DoS with unexpected TLS packet

Details

Apache Tomcat 8.5.0 to 8.5.63, 9.0.0 to 9.0.43 and 10.0.0 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.

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "Bitnami",
        "name": "tomcat",
        "purl": "pkg:bitnami/tomcat"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "8.5.0"
            },
            {
              "fixed": "8.5.64"
            },
            {
              "introduced": "9.0.0"
            },
            {
              "fixed": "9.0.44"
            },
            {
              "introduced": "10.0.0"
            },
            {
              "fixed": "10.0.3"
            }
          ],
          "type": "SEMVER"
        }
      ],
      "severity": [
        {
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "type": "CVSS_V3"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2021-41079"
  ],
  "database_specific": {
    "cpes": [
      "cpe:2.3:a:apache:tomcat:*:*:*:*:*:*:*:*"
    ],
    "severity": "High"
  },
  "details": "Apache Tomcat 8.5.0 to 8.5.63, 9.0.0 to 9.0.43 and 10.0.0 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.",
  "id": "BIT-tomcat-2021-41079",
  "modified": "2026-09-08T08:34:36.952Z",
  "published": "2024-03-06T11:09:56.377Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://lists.apache.org/thread.html/r6b6b674e3f168dd010e67dbe6848b866e2acf26371452fdae313b98a%40%3Cusers.tomcat.apache.org%3E"
    },
    {
      "type": "WEB",
      "url": "https://lists.apache.org/thread.html/rb4de81ac647043541a32881099aa6eb5a23f1b7fd116f713f8ab9dbe%40%3Cdev.tomcat.apache.org%3E"
    },
    {
      "type": "ADVISORY",
      "url": "https://lists.apache.org/thread.html/rccdef0349fdf4fb73a4e4403095446d7fe6264e0a58e2df5c6799434%40%3Cannounce.tomcat.apache.org%3E"
    },
    {
      "type": "ADVISORY",
      "url": "https://lists.debian.org/debian-lts-announce/2021/09/msg00012.html"
    },
    {
      "type": "ADVISORY",
      "url": "https://security.netapp.com/advisory/ntap-20211008-0005/"
    },
    {
      "type": "ADVISORY",
      "url": "https://www.debian.org/security/2021/dsa-4986"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-41079"
    }
  ],
  "schema_version": "1.5.0",
  "summary": "Apache Tomcat DoS with unexpected TLS packet"
}

CVE-2021-41079 (GCVE-0-2021-41079)

Vulnerability from cvelistv5 – Published: 2021-09-16 14:40 – Updated: 2026-10-08 21:13

Title

Apache Tomcat DoS with unexpected TLS packet

Summary

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.

Severity

No CVSS data available.

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-10-08 21:06 UTC

CWE

CWE-20 - Improper Input Validation

Assigner

apache CNA under the mitre root

CNA scorecard B 76/100 over 1086 records in the last 180 days details

References

6 references

URL	Tags
https://lists.apache.org/thread.html/rccdef0349fd…	x_refsource_MISC
https://lists.debian.org/debian-lts-announce/2021…	mailing-listx_refsource_MLIST
https://security.netapp.com/advisory/ntap-2021100…	x_refsource_CONFIRM
https://lists.apache.org/thread.html/rb4de81ac647…	mailing-listx_refsource_MLIST
https://lists.apache.org/thread.html/r6b6b674e3f1…	mailing-listx_refsource_MLIST
https://www.debian.org/security/2021/dsa-4986	vendor-advisoryx_refsource_DEBIAN

Impacted products

1 product

Vendor	Product	Version
Apache Software Foundation	Apache Tomcat	Affected: Apache Tomcat 8.5 8.5.0 to 8.5.63 Affected: Apache Tomcat 9 9.0.0-M1 to 9.0.43 Affected: Apache Tomcat 10 10.0.0-M1 to 10.0.2

Credits

The Apache Tomcat security team would like to thank Thomas Wozenilek for originally reporting this issue and David Frankson of Infinite Campus for also providing a test case that reproduced the issue.

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Vulnerability timeline

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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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