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CVE-2021-41524 (GCVE-0-2021-41524)

Vulnerability from cvelistv5 – Published: 2021-10-05 08:40 – Updated: 2024-08-04 03:15
VLAI
Title
null pointer dereference in h2 fuzzing
Summary
While fuzzing the 2.4.49 httpd, a new null pointer dereference was detected during HTTP/2 request processing, allowing an external source to DoS the server. This requires a specially crafted request. The vulnerability was recently introduced in version 2.4.49. No exploit is known to the project.
Severity
No CVSS data available.
CWE
  • CWE-476 - NULL Pointer Dereference
Assigner
References
Impacted products
Vendor Product Version CPE status
Apache Software Foundation Apache HTTP Server Affected: 2.4.49
guessed Create a notification for this product.
Credits
Apache httpd team would like to thank LI ZHI XIN from NSFocus Security Team for reporting this issue.
Show details on NVD website
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Server\",\"versions\":[{\"version\":\"2.4.49\",\"status\":\"affected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H\",\"baseScore\":7.5,\"baseSeverity\":\"HIGH\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":3.9,\"impactScore\":3.6}],\"cvssMetricV2\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"cvssData\":{\"version\":\"2.0\",\"vectorString\":\"AV:N/AC:L/Au:N/C:N/I:N/A:P\",\"baseScore\":5.0,\"accessVector\":\"NETWORK\",\"accessComplexity\":\"LOW\",\"authentication\":\"NONE\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"PARTIAL\"},\"baseSeverity\":\"MEDIUM\",\"exploitabilityScore\":10.0,\"impactScore\":2.9,\"acInsufInfo\":false,\"obtainAllPrivilege\":false,\"obtainUserPrivilege\":false,\"obtainOtherPrivilege\":false,\"userInteractionRequired\":false}]},\"weaknesses\":[{\"source\":\"security@apache.org\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-476\"}]},{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-476\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:apache:http_server:2.4.49:*:*:*:*:*:*:*\",\"matchCriteriaId\":\"B201CFB2-F626-4DD0-9F6A-DFE8F64203E2\"}]}]},{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*\",\"matchCriteriaId\":\"A930E247-0B43-43CB-98FF-6CE7B8189835\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*\",\"matchCriteriaId\":\"80E516C0-98A4-4ADE-B69F-66A772E2BAAA\"}]}]},{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:oracle:instantis_enterprisetrack:17.1:*:*:*:*:*:*:*\",\"matchCriteriaId\":\"82EA4BA7-C38B-4AF3-8914-9E3D089EBDD4\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:oracle:instantis_enterprisetrack:17.2:*:*:*:*:*:*:*\",\"matchCriteriaId\":\"B9C9BC66-FA5F-4774-9BDA-7AB88E2839C4\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:oracle:instantis_enterprisetrack:17.3:*:*:*:*:*:*:*\",\"matchCriteriaId\":\"7F69B9A5-F21B-4904-9F27-95C0F7A628E3\"}]}]},{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:netapp:cloud_backup:-:*:*:*:*:*:*:*\",\"matchCriteriaId\":\"5C2089EE-5D7F-47EC-8EA5-0F69790564C4\"}]}]}],\"references\":[{\"url\":\"http://www.openwall.com/lists/oss-security/2021/10/05/1\",\"source\":\"security@apache.org\",\"tags\":[\"Mailing List\",\"Third Party Advisory\"]},{\"url\":\"https://httpd.apache.org/security/vulnerabilities_24.html\",\"source\":\"security@apache.org\",\"tags\":[\"Vendor Advisory\"]},{\"url\":\"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/DSM6UWQICBJ2TU727RENU3HBKEAFLT6T/\",\"source\":\"security@apache.org\"},{\"url\":\"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/EUVJVRJRBW5QVX4OY3NOHZDQ3B3YOTSG/\",\"source\":\"security@apache.org\"},{\"url\":\"https://security.gentoo.org/glsa/202208-20\",\"source\":\"security@apache.org\",\"tags\":[\"Third Party Advisory\"]},{\"url\":\"https://security.netapp.com/advisory/ntap-20211029-0009/\",\"source\":\"security@apache.org\",\"tags\":[\"Third Party Advisory\"]},{\"url\":\"https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-apache-httpd-pathtrv-LAzg68cZ\",\"source\":\"security@apache.org\",\"tags\":[\"Third Party Advisory\"]},{\"url\":\"https://www.oracle.com/security-alerts/cpujan2022.html\",\"source\":\"security@apache.org\",\"tags\":[\"Patch\",\"Third Party Advisory\"]},{\"url\":\"http://www.openwall.com/lists/oss-security/2021/10/05/1\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Mailing List\",\"Third Party Advisory\"]},{\"url\":\"https://httpd.apache.org/security/vulnerabilities_24.html\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Vendor 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Advisory\"]},{\"url\":\"https://www.oracle.com/security-alerts/cpujan2022.html\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Patch\",\"Third Party Advisory\"]}]}}",
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-06-28T07:49:01+00:00",
      "cve": "CVE-2021-41524",
      "id": "CVE-2021-41524",
      "initial_release_date": "2021-10-05T00:00:00+00:00",
      "product_status:fixed": "28",
      "product_status:known_affected": "7",
      "product_status:known_not_affected": "180",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "httpd: NULL pointer dereference via crafted request during HTTP/2 request processing",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2021/cve-2021-41524.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "important",
      "current_release_date": "2026-07-25T17:39:00Z",
      "cve": "CVE-2021-41524",
      "id": "CVE-2021-41524",
      "initial_release_date": "2023-02-15T03:37:28Z",
      "product_status:known_not_affected": "235",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2021-41524",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2021-41524.json",
      "version": "11"
    }
  }
}



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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.


Detection rules are retrieved from Rulezet.


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.