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For users unable to upgrade the execution time can be bounded by limiting the maximum length of an input to any of the vulnerable functions. Our recommendation is to implement such a limit."}], "metrics": [{"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}}], "problemTypes": [{"descriptions": [{"cweId": "CWE-400", "description": "CWE-400: Uncontrolled Resource Consumption", "lang": "en", "type": "CWE"}]}], "providerMetadata": {"dateUpdated": "2021-12-23T17:55:11", "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M"}, "references": [{"tags": ["x_refsource_CONFIRM"], "url": "https://github.com/nltk/nltk/security/advisories/GHSA-f8m6-h2c7-8h9x"}, {"tags": ["x_refsource_MISC"], "url": "https://github.com/nltk/nltk/issues/2866"}, {"tags": ["x_refsource_MISC"], "url": "https://github.com/nltk/nltk/pull/2869"}, {"tags": ["x_refsource_MISC"], "url": "https://github.com/nltk/nltk/commit/1405aad979c6b8080dbbc8e0858f89b2e3690341"}], "source": {"advisory": "GHSA-f8m6-h2c7-8h9x", "discovery": "UNKNOWN"}, "title": "Inefficient Regular Expression Complexity in nltk", "x_legacyV4Record": {"CVE_data_meta": {"ASSIGNER": "security-advisories@github.com", "ID": "CVE-2021-43854", "STATE": "PUBLIC", "TITLE": "Inefficient Regular Expression Complexity in nltk"}, "affects": {"vendor": {"vendor_data": [{"product": {"product_data": [{"product_name": "nltk", "version": {"version_data": [{"version_value": "< 3.6.5"}]}}]}, "vendor_name": "nltk"}]}}, "data_format": "MITRE", "data_type": "CVE", "data_version": "4.0", "description": {"description_data": [{"lang": "eng", "value": "NLTK (Natural Language Toolkit) is a suite of open source Python modules, data sets, and tutorials supporting research and development in Natural Language Processing. 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Our recommendation is to implement such a limit."}]}, "impact": {"cvss": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}}, "problemtype": {"problemtype_data": [{"description": [{"lang": "eng", "value": "CWE-400: Uncontrolled Resource Consumption"}]}]}, "references": {"reference_data": [{"name": "https://github.com/nltk/nltk/security/advisories/GHSA-f8m6-h2c7-8h9x", "refsource": "CONFIRM", "url": "https://github.com/nltk/nltk/security/advisories/GHSA-f8m6-h2c7-8h9x"}, {"name": "https://github.com/nltk/nltk/issues/2866", "refsource": "MISC", "url": "https://github.com/nltk/nltk/issues/2866"}, {"name": "https://github.com/nltk/nltk/pull/2869", "refsource": "MISC", "url": "https://github.com/nltk/nltk/pull/2869"}, {"name": "https://github.com/nltk/nltk/commit/1405aad979c6b8080dbbc8e0858f89b2e3690341", "refsource": "MISC", "url": "https://github.com/nltk/nltk/commit/1405aad979c6b8080dbbc8e0858f89b2e3690341"}]}, "source": {"advisory": "GHSA-f8m6-h2c7-8h9x", "discovery": "UNKNOWN"}}}}, "cveMetadata": {"assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "assignerShortName": "GitHub_M", "cveId": "CVE-2021-43854", "datePublished": "2021-12-23T17:55:11", "dateReserved": "2021-11-16T00:00:00", "dateUpdated": "2021-12-23T17:55:11", "state": "PUBLISHED"}, "dataType": "CVE_RECORD", "dataVersion": "5.0"}

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