{
  "affected": [
    {
      "database_specific": {
        "source": "https://cna.erlef.org/osv/EEF-CVE-2026-65626.json"
      },
      "package": {
        "ecosystem": "Hex",
        "name": "jose",
        "purl": "pkg:hex/jose"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "1.3.0"
            },
            {
              "fixed": "1.11.13"
            }
          ],
          "type": "SEMVER"
        }
      ],
      "versions": [
        "1.10.0",
        "1.10.1",
        "1.11.0",
        "1.11.1",
        "1.11.10",
        "1.11.11",
        "1.11.12",
        "1.11.2",
        "1.11.4",
        "1.11.5",
        "1.11.6",
        "1.11.7",
        "1.11.8",
        "1.11.9",
        "1.3.0",
        "1.4.0",
        "1.4.1",
        "1.4.2",
        "1.5.0",
        "1.5.1",
        "1.5.2",
        "1.6.0",
        "1.6.1",
        "1.7.0",
        "1.7.1",
        "1.7.2",
        "1.7.3",
        "1.7.4",
        "1.7.5",
        "1.7.6",
        "1.7.7",
        "1.7.8",
        "1.7.9",
        "1.8.0",
        "1.8.1",
        "1.8.2",
        "1.8.3",
        "1.8.4",
        "1.9.0"
      ]
    },
    {
      "database_specific": {
        "source": "https://cna.erlef.org/osv/EEF-CVE-2026-65626.json"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "853c5d4c4c0bd2a7ecb055b237f4284184e176c8"
            },
            {
              "fixed": "0eac8cef9aaa48fb6846f4e47a0002dc4a73966d"
            }
          ],
          "repo": "https://github.com/potatosalad/erlang-jose",
          "type": "GIT"
        }
      ],
      "versions": [
        "1.11.12",
        "1.11.11",
        "1.11.10",
        "1.11.9",
        "1.11.8",
        "1.11.7",
        "1.11.5",
        "1.11.4",
        "1.11.2",
        "1.11.1",
        "1.11.0",
        "1.10.1",
        "1.10.0",
        "1.9.0",
        "1.8.4",
        "1.8.3",
        "1.8.2",
        "1.8.1",
        "1.8.0",
        "1.7.9",
        "1.7.8",
        "1.7.7",
        "1.7.6",
        "1.7.5",
        "1.7.4",
        "1.7.3",
        "1.7.2",
        "1.7.1",
        "1.7.0",
        "1.6.1",
        "1.6.0",
        "1.5.2",
        "1.5.1",
        "1.5.0",
        "1.4.2",
        "1.4.1",
        "1.4.0",
        "1.3.0"
      ]
    }
  ],
  "aliases": [
    "CVE-2026-65626",
    "GHSA-vwvr-f994-6j9j"
  ],
  "credits": [
    {
      "name": "Peter Ullrich",
      "type": "REPORTER"
    },
    {
      "name": "Andrew Bennett",
      "type": "REMEDIATION_DEVELOPER"
    },
    {
      "name": "Jonatan Männchen / EEF",
      "type": "ANALYST"
    }
  ],
  "database_specific": {
    "capec_ids": [
      "CAPEC-463"
    ],
    "cpe_ids": [
      "cpe:2.3:a:potatosalad:jose:*:*:*:*:*:*:*:*"
    ],
    "cwe_ids": [
      "CWE-203"
    ]
  },
  "details": "## Summary\n\nThe 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.\n\n## Configurations\n\nThe vulnerable code path is only reached when jose performs RSAES-PKCS1-v1_5 decryption with its pure-Erlang fallback (the `jose_jwa_pkcs1` module) instead of the native OTP `public_key` implementation. This requires the crypto_fallback option to be enabled (`application:set_env(jose, crypto_fallback, true)`, or `JOSE.crypto_fallback(true)` in Elixir) and the OTP runtime not to provide native RSA1_5 decryption. When native OTP RSA support is selected, decryption does not go through `jose_jwa_pkcs1`.",
  "id": "EEF-CVE-2026-65626",
  "modified": "2026-10-26T20:11:07.651789963Z",
  "published": "2026-10-26T19:53:05.620Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/potatosalad/erlang-jose/security/advisories/GHSA-vwvr-f994-6j9j"
    },
    {
      "type": "WEB",
      "url": "https://cna.erlef.org/cves/CVE-2026-65626.html"
    },
    {
      "type": "WEB",
      "url": "https://github.com/potatosalad/erlang-jose/commit/853c5d4c4c0bd2a7ecb055b237f4284184e176c8"
    },
    {
      "type": "FIX",
      "url": "https://github.com/potatosalad/erlang-jose/commit/0eac8cef9aaa48fb6846f4e47a0002dc4a73966d"
    },
    {
      "type": "PACKAGE",
      "url": "https://hex.pm/packages/jose"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "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",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Bleichenbacher padding oracle in RSAES-PKCS1-v1_5 decryption in jose"
}