OESA-2021-1464 (CVE-2021-42717)

Vulnerability from osv_openeuler – Published: 2021-12-17 11:04 – Updated: 2026-08-06 11:04 – Source website
VLAI
Summary
mod_security security update
Details

This software is also called Modsec,it is an open-source web application firewall. It is designed for Apache HTTP Server.ModSecurity is commonly deployed to provide protections against generic classed of vulnerabilities.The install of this package is easy and you can read the README.TXT for more information.

Security Fix(es):

ModSecurity 3.x through 3.0.5 mishandles excessively nested JSON objects. Crafted JSON objects with nesting tens-of-thousands deep could result in the web server being unable to service legitimate requests. Even a moderately large (e.g., 300KB) HTTP request can occupy one of the limited NGINX worker processes for minutes and consume almost all of the available CPU on the machine. Modsecurity 2 is similarly vulnerable: the affected versions include 2.8.0 through 2.9.4.(CVE-2021-42717)

Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "aarch64": [
          "mod_security-debugsource-2.9.5-1.oe1.aarch64.rpm",
          "mod_security-2.9.5-1.oe1.aarch64.rpm",
          "mod_security-debuginfo-2.9.5-1.oe1.aarch64.rpm"
        ],
        "src": [
          "mod_security-2.9.5-1.oe1.src.rpm"
        ],
        "x86_64": [
          "mod_security-debugsource-2.9.5-1.oe1.x86_64.rpm",
          "mod_security-2.9.5-1.oe1.x86_64.rpm",
          "mod_security-debuginfo-2.9.5-1.oe1.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:20.03-LTS-SP1",
        "name": "mod_security",
        "purl": "pkg:rpm/openEuler/mod_security\u0026distro=openEuler-20.03-LTS-SP1"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.9.5-1.oe1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "aarch64": [
          "mod_security-debuginfo-2.9.5-1.oe1.aarch64.rpm",
          "mod_security-2.9.5-1.oe1.aarch64.rpm",
          "mod_security-debugsource-2.9.5-1.oe1.aarch64.rpm"
        ],
        "src": [
          "mod_security-2.9.5-1.oe1.src.rpm"
        ],
        "x86_64": [
          "mod_security-2.9.5-1.oe1.x86_64.rpm",
          "mod_security-debugsource-2.9.5-1.oe1.x86_64.rpm",
          "mod_security-debuginfo-2.9.5-1.oe1.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:20.03-LTS-SP2",
        "name": "mod_security",
        "purl": "pkg:rpm/openEuler/mod_security\u0026distro=openEuler-20.03-LTS-SP2"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.9.5-1.oe1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "severity": "High"
  },
  "details": "This software is also called Modsec,it is an open-source web application firewall. It is designed for Apache HTTP Server.ModSecurity is commonly deployed to provide protections against generic classed of vulnerabilities.The install of this package is easy and you can read the README.TXT for more information.\r\n\r\nSecurity Fix(es):\r\n\r\nModSecurity 3.x through 3.0.5 mishandles excessively nested JSON objects. Crafted JSON objects with nesting tens-of-thousands deep could result in the web server being unable to service legitimate requests. Even a moderately large (e.g., 300KB) HTTP request can occupy one of the limited NGINX worker processes for minutes and consume almost all of the available CPU on the machine. Modsecurity 2 is similarly vulnerable: the affected versions include 2.8.0 through 2.9.4.(CVE-2021-42717)",
  "id": "OESA-2021-1464",
  "modified": "2026-08-06T11:04:44Z",
  "published": "2021-12-17T11:04:44Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.openeuler.org/en/security/safety-bulletin/detail.html?id=openEuler-SA-2021-1464"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-42717"
    }
  ],
  "schema_version": "1.7.2",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "mod_security security update",
  "upstream": [
    "CVE-2021-42717"
  ]
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





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

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.



Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.