{"id":"CVE-2026-65626","revision":"9a91181b2f124e8f8ef5280fe53ba1de","records":[{"revision":"9a91181b2f124e8f8ef5280fe53ba1de","observedAt":"2026-10-26T20:35:31.018+00:00","statement":{"source":"cve-program","id":"CVE-2026-65626","aliases":[],"title":"Bleichenbacher padding oracle in RSAES-PKCS1-v1_5 decryption in jose","description":"The pure-Erlang RSAES-PKCS1-v1_5 decryption in the jose_jwa_pkcs1 module is a Bleichenbacher padding oracle. eme_pkcs1_decode/2 returns the recovered message when a decrypted block has valid PKCS#1 v1.5 padding (a leading 0x00 0x02, a padding string of at least eight non-zero bytes, and a 0x00 separator) and returns a distinct error result otherwise, and rsaes_pkcs1_decrypt/2 additionally returns {error, {badsize, _}} when the length check fails. The implementation applies no implicit-rejection countermeasure (RFC 8017 §7.2.2): it does not substitute a deterministic pseudo-random plaintext on a padding failure, so a one-bit padding-conformance signal leaks to the caller. Because the underlying modular exponentiation in dp/2 is a raw, non-blinded crypto:mod_pow/3, the padding check also stays distinguishable by timing even when an application normalizes every failure to a single error value.\n\nAn unauthenticated attacker who knows only the public RSA key and can submit ciphertexts to a decryption endpoint that unwraps RSA1_5 JWE keys (or otherwise calls decrypt_private/3 with rsa_pkcs1_padding) can use this oracle to recover the plaintext of intercepted ciphertexts, such as content-encryption keys and thus the protected message, or to forge signatures, through roughly 10^4 to 10^6 adaptive chosen-ciphertext queries.\n\nThis issue affects jose: from 1.3.0 before 1.11.13.","state":0,"publishedAt":"2026-10-26T19:53:05.62+00:00","modifiedAt":"2026-10-26T19:53:05.62+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_jwa_pkcs1\"\n                    ],\n                    \"packageName\": \"jose\",\n                    \"packageURL\": \"pkg:hex/jose\",\n                    \"product\": \"jose\",\n                    \"programFiles\": [\n                        \"src/jwa/jose_jwa_pkcs1.erl\"\n                    ],\n                    \"programRoutines\": [\n                        {\n                            \"name\": \"jose_jwa_pkcs1:decrypt_private/3\"\n                        },\n                        {\n                            \"name\": \"jose_jwa_pkcs1:rsaes_pkcs1_decrypt/2\"\n                        },\n                        {\n                            \"name\": \"jose_jwa_pkcs1:eme_pkcs1_decode/2\"\n                        },\n                        {\n                            \"name\": \"jose_jwa_pkcs1:dp/2\"\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\": \"1.3.0\",\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_jwa_pkcs1\"\n                    ],\n                    \"packageName\": \"potatosalad/erlang-jose\",\n                    \"packageURL\": \"pkg:github/potatosalad/erlang-jose\",\n                    \"product\": \"jose\",\n                    \"programFiles\": [\n                        \"src/jwa/jose_jwa_pkcs1.erl\"\n                    ],\n                    \"programRoutines\": [\n                        {\n                            \"name\": \"jose_jwa_pkcs1:decrypt_private/3\"\n                        },\n                        {\n                            \"name\": \"jose_jwa_pkcs1:rsaes_pkcs1_decrypt/2\"\n                        },\n                        {\n                            \"name\": \"jose_jwa_pkcs1:eme_pkcs1_decode/2\"\n                        },\n                        {\n                            \"name\": \"jose_jwa_pkcs1:dp/2\"\n                        }\n                    ],\n                    \"repo\": \"https://github.com/potatosalad/erlang-jose\",\n                    \"vendor\": \"potatosalad\",\n                    \"versions\": [\n                        {\n                            \"lessThan\": \"0eac8cef9aaa48fb6846f4e47a0002dc4a73966d\",\n                            \"status\": \"affected\",\n                            \"version\": \"853c5d4c4c0bd2a7ecb055b237f4284184e176c8\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 4.0","vector":"CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N","score":5.9,"severity":"MEDIUM"}],"references":["https://github.com/potatosalad/erlang-jose/security/advisories/GHSA-vwvr-f994-6j9j","https://cna.erlef.org/cves/CVE-2026-65626.html","https://osv.dev/vulnerability/EEF-CVE-2026-65626","https://github.com/potatosalad/erlang-jose/commit/853c5d4c4c0bd2a7ecb055b237f4284184e176c8","https://github.com/potatosalad/erlang-jose/commit/0eac8cef9aaa48fb6846f4e47a0002dc4a73966d"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-65626","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-65626","identifiers":["CVE-2026-65626"]},"retained":false,"historicalAffected":[]}],"coverage":[]}