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Vulnerability from bitnami_vulndb
Published
2024-03-06 11:10
Modified
2026-09-08 08:34
Summary
DoS after non-blocking IO error
Details

A vulnerability in Apache Tomcat allows an attacker to remotely trigger a denial of service. An error introduced as part of a change to improve error handling during non-blocking I/O meant that the error flag associated with the Request object was not reset between requests. This meant that once a non-blocking I/O error occurred, all future requests handled by that request object would fail. Users were able to trigger non-blocking I/O errors, e.g. by dropping a connection, thereby creating the possibility of triggering a DoS. Applications that do not use non-blocking I/O are not exposed to this vulnerability. This issue affects Apache Tomcat 10.0.3 to 10.0.4; 9.0.44; 8.5.64.

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{
  "affected": [
    {
      "package": {
        "ecosystem": "Bitnami",
        "name": "tomcat",
        "purl": "pkg:bitnami/tomcat"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "8.5.64"
            },
            {
              "fixed": "8.5.65"
            },
            {
              "introduced": "9.0.44"
            },
            {
              "fixed": "9.0.45"
            },
            {
              "introduced": "10.0.3"
            },
            {
              "fixed": "10.0.4"
            },
            {
              "introduced": "10.0.4"
            },
            {
              "fixed": "10.0.5"
            }
          ],
          "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-2021-30639"
  ],
  "database_specific": {
    "cpes": [
      "cpe:2.3:a:apache:tomcat:10.0.3:*:*:*:*:*:*:*",
      "cpe:2.3:a:apache:tomcat:10.0.4:*:*:*:*:*:*:*",
      "cpe:2.3:a:apache:tomcat:8.5.64:*:*:*:*:*:*:*",
      "cpe:2.3:a:apache:tomcat:9.0.44:*:*:*:*:*:*:*",
      "cpe:2.3:a:apache:tomcat:*:*:*:*:*:*:*:*"
    ],
    "severity": "High"
  },
  "details": "A vulnerability in Apache Tomcat allows an attacker to remotely trigger a denial of service. An error introduced as part of a change to improve error handling during non-blocking I/O meant that the error flag associated with the Request object was not reset between requests. This meant that once a non-blocking I/O error occurred, all future requests handled by that request object would fail. Users were able to trigger non-blocking I/O errors, e.g. by dropping a connection, thereby creating the possibility of triggering a DoS. Applications that do not use non-blocking I/O are not exposed to this vulnerability. This issue affects Apache Tomcat 10.0.3 to 10.0.4; 9.0.44; 8.5.64.",
  "id": "BIT-tomcat-2021-30639",
  "modified": "2026-09-08T08:34:36.952Z",
  "published": "2024-03-06T11:10:12.195Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://kc.mcafee.com/corporate/index?page=content\u0026id=SB10366"
    },
    {
      "type": "WEB",
      "url": "https://lists.apache.org/thread.html/r79a7c019712b39aedf7cf4da9276d80610f04441b2a4f6506cb2daaf%40%3Cdev.tomcat.apache.org%3E"
    },
    {
      "type": "WEB",
      "url": "https://lists.apache.org/thread.html/r79a7c019712b39aedf7cf4da9276d80610f04441b2a4f6506cb2daaf%40%3Cusers.tomcat.apache.org%3E"
    },
    {
      "type": "ADVISORY",
      "url": "https://lists.apache.org/thread.html/rd84fae1f474597bdf358f5bdc0a5c453c507bd527b83e8be6b5ea3f4%40%3Cannounce.tomcat.apache.org%3E"
    },
    {
      "type": "ADVISORY",
      "url": "https://security.gentoo.org/glsa/202208-34"
    },
    {
      "type": "ADVISORY",
      "url": "https://security.netapp.com/advisory/ntap-20210827-0007/"
    },
    {
      "type": "ADVISORY",
      "url": "https://www.oracle.com/security-alerts/cpujan2022.html"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-30639"
    }
  ],
  "schema_version": "1.5.0",
  "summary": "DoS after non-blocking IO error"
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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