{"id":"CVE-2023-3817","revision":"ab5c4bb614a94fcaa02a71eb07c6bf09","records":[{"revision":"ab5c4bb614a94fcaa02a71eb07c6bf09","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2023-3817","aliases":[],"title":"Excessive time spent checking DH q parameter value","description":"Issue summary: Checking excessively long DH keys or parameters may be very slow.\n\nImpact summary: Applications that use the functions DH_check(), DH_check_ex()\nor EVP_PKEY_param_check() to check a DH key or DH parameters may experience long\ndelays. Where the key or parameters that are being checked have been obtained\nfrom an untrusted source this may lead to a Denial of Service.\n\nThe function DH_check() performs various checks on DH parameters. After fixing\nCVE-2023-3446 it was discovered that a large q parameter value can also trigger\nan overly long computation during some of these checks. A correct q value,\nif present, cannot be larger than the modulus p parameter, thus it is\nunnecessary to perform these checks if q is larger than p.\n\nAn application that calls DH_check() and supplies a key or parameters obtained\nfrom an untrusted source could be vulnerable to a Denial of Service attack.\n\nThe function DH_check() is itself called by a number of other OpenSSL functions.\nAn application calling any of those other functions may similarly be affected.\nThe other functions affected by this are DH_check_ex() and\nEVP_PKEY_param_check().\n\nAlso vulnerable are the OpenSSL dhparam and pkeyparam command line applications\nwhen using the \"-check\" option.\n\nThe OpenSSL SSL/TLS implementation is not affected by this issue.\n\nThe OpenSSL 3.0 and 3.1 FIPS providers are not affected by this issue.","state":0,"publishedAt":"2023-07-31T15:34:13.627+00:00","modifiedAt":"2026-10-14T21:13:47.977+00:00","affected":[{"ecosystem":"Vendor product","name":"OpenSSL","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"defaultStatus\": \"unaffected\",\n                    \"product\": \"OpenSSL\",\n                    \"vendor\": \"OpenSSL\",\n                    \"versions\": [\n                        {\n                            \"lessThan\": \"3.1.2\",\n                            \"status\": \"affected\",\n                            \"version\": \"3.1.0\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"lessThan\": \"3.0.10\",\n                            \"status\": \"affected\",\n                            \"version\": \"3.0.0\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"lessThan\": \"1.1.1v\",\n                            \"status\": \"affected\",\n                            \"version\": \"1.1.1\",\n                            \"versionType\": \"custom\"\n                        },\n                        {\n                            \"lessThan\": \"1.0.2zi\",\n                            \"status\": \"affected\",\n                            \"version\": \"1.0.2\",\n                            \"versionType\": \"custom\"\n                        }\n                    ]\n                }"}],"metrics":[],"references":["https://www.openssl.org/news/secadv/20230731.txt","https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=6a1eb62c29db6cb5eec707f9338aee00f44e26f5","https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=9002fd07327a91f35ba6c1307e71fa6fd4409b7f","https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=91ddeba0f2269b017dc06c46c993a788974b1aa5","https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=869ad69aadd985c7b8ca6f4e5dd0eb274c9f3644"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2023-3817","license":"CVE Program Terms of Use","key":"cve-program:CVE-2023-3817","identifiers":["CVE-2023-3817"]},"retained":false,"historicalAffected":[]}],"coverage":[]}