{"id":"CVE-2026-65631","revision":"b1a45ac7d28844c69c40529efd71f96a","records":[{"revision":"b1a45ac7d28844c69c40529efd71f96a","observedAt":"2026-10-26T20:35:31.018+00:00","statement":{"source":"cve-program","id":"CVE-2026-65631","aliases":[],"title":"erlang-jose RSA JWK parsing attempts to factor an attacker-controlled modulus, enabling CPU-exhaustion denial of service","description":"Inefficient Algorithmic Complexity in erlang-jose allows an unauthenticated remote attacker to cause a CPU-exhaustion denial of service by submitting a crafted RSA JSON Web Key.\n\nWhen an application parses an untrusted JWK through the public jose_jwk:from_binary/1 or jose_jwk:from_map/1 API (or the Elixir wrappers JOSE.JWK.from_binary/1 and JOSE.JWK.from_map/1), an RSA private key that supplies d, e, and n but omits all Chinese Remainder Theorem parameters (p, q, dp, dq, qi) is routed into convert_sfm_to_crt/1, which tries to recover the missing primes by factoring the modulus. The three integers are read straight from the base64url input and are never validated as a real RSA key. When the modulus cannot be split into two factors (for example, when it is itself prime), the search loop convert_sfm_to_crt_find_p/6 performs a modular exponentiation over the attacker-sized modulus on every iteration and never succeeds. A single request of a few hundred bytes forces close to one CPU-second of work before an internal one-second watchdog kills the worker, and a larger modulus raises the cost further. By flooding such requests an attacker can saturate every scheduler and deny service, without credentials, a valid RSA key, or any special configuration.\n\nThis issue affects jose: from 1.7.7 before 1.11.13.","state":0,"publishedAt":"2026-10-26T19:53:45.204+00:00","modifiedAt":"2026-10-26T19:53:45.204+00:00","affected":[{"ecosystem":"https://repo.hex.pm","name":"jose","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"collectionURL\": \"https://repo.hex.pm\",\n                    \"cpes\": [\n                        \"cpe:2.3:a:potatosalad:jose:*:*:*:*:*:*:*:*\"\n                    ],\n                    \"defaultStatus\": \"unaffected\",\n                    \"modules\": [\n                        \"jose_jwk_kty_rsa\",\n                        \"jose_jwk\",\n                        \"'Elixir.JOSE.JWK'\"\n                    ],\n                    \"packageName\": \"jose\",\n                    \"packageURL\": \"pkg:hex/jose\",\n                    \"product\": \"jose\",\n                    \"programFiles\": [\n                        \"src/jwk/jose_jwk_kty_rsa.erl\",\n                        \"src/jwk/jose_jwk.erl\",\n                        \"lib/jose/jwk.ex\"\n                    ],\n                    \"programRoutines\": [\n                        {\n                            \"name\": \"jose_jwk_kty_rsa:from_map/1\"\n                        },\n                        {\n                            \"name\": \"jose_jwk_kty_rsa:convert_sfm_to_crt/1\"\n                        },\n                        {\n                            \"name\": \"jose_jwk_kty_rsa:convert_sfm_to_crt_find_p/6\"\n                        },\n                        {\n                            \"name\": \"jose_jwk:from_binary/1\"\n                        },\n                        {\n                            \"name\": \"jose_jwk:from_map/1\"\n                        },\n                        {\n                            \"name\": \"'Elixir.JOSE.JWK':from_binary/1\"\n                        },\n                        {\n                            \"name\": \"'Elixir.JOSE.JWK':from_map/1\"\n                        }\n                    ],\n                    \"repo\": \"https://github.com/potatosalad/erlang-jose\",\n                    \"vendor\": \"potatosalad\",\n                    \"versions\": [\n                        {\n                            \"lessThan\": \"1.11.13\",\n                            \"status\": \"affected\",\n                            \"version\": \"1.7.7\",\n                            \"versionType\": \"semver\"\n                        }\n                    ]\n                }"},{"ecosystem":"https://github.com","name":"potatosalad/erlang-jose","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"collectionURL\": \"https://github.com\",\n                    \"cpes\": [\n                        \"cpe:2.3:a:potatosalad:jose:*:*:*:*:*:*:*:*\"\n                    ],\n                    \"defaultStatus\": \"unaffected\",\n                    \"modules\": [\n                        \"jose_jwk_kty_rsa\",\n                        \"jose_jwk\",\n                        \"'Elixir.JOSE.JWK'\"\n                    ],\n                    \"packageName\": \"potatosalad/erlang-jose\",\n                    \"packageURL\": \"pkg:github/potatosalad/erlang-jose\",\n                    \"product\": \"jose\",\n                    \"programFiles\": [\n                        \"src/jwk/jose_jwk_kty_rsa.erl\",\n                        \"src/jwk/jose_jwk.erl\",\n                        \"lib/jose/jwk.ex\"\n                    ],\n                    \"programRoutines\": [\n                        {\n                            \"name\": \"jose_jwk_kty_rsa:from_map/1\"\n                        },\n                        {\n                            \"name\": \"jose_jwk_kty_rsa:convert_sfm_to_crt/1\"\n                        },\n                        {\n                            \"name\": \"jose_jwk_kty_rsa:convert_sfm_to_crt_find_p/6\"\n                        },\n                        {\n                            \"name\": \"jose_jwk:from_binary/1\"\n                        },\n                        {\n                            \"name\": \"jose_jwk:from_map/1\"\n                        },\n                        {\n                            \"name\": \"'Elixir.JOSE.JWK':from_binary/1\"\n                        },\n                        {\n                            \"name\": \"'Elixir.JOSE.JWK':from_map/1\"\n                        }\n                    ],\n                    \"repo\": \"https://github.com/potatosalad/erlang-jose\",\n                    \"vendor\": \"potatosalad\",\n                    \"versions\": [\n                        {\n                            \"lessThan\": \"bfd336c0062bff93e65d08c22361897e96afd956\",\n                            \"status\": \"affected\",\n                            \"version\": \"d19e1ba68d88c68d29aa942be2573a22dbafca1f\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 4.0","vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","score":6.9,"severity":"MEDIUM"}],"references":["https://github.com/potatosalad/erlang-jose/security/advisories/GHSA-3m45-vrpj-xmrq","https://cna.erlef.org/cves/CVE-2026-65631.html","https://osv.dev/vulnerability/EEF-CVE-2026-65631","https://github.com/potatosalad/erlang-jose/commit/d19e1ba68d88c68d29aa942be2573a22dbafca1f","https://github.com/potatosalad/erlang-jose/commit/bfd336c0062bff93e65d08c22361897e96afd956"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-65631","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-65631","identifiers":["CVE-2026-65631"]},"retained":false,"historicalAffected":[]}],"coverage":[]}