{"id":"CVE-2026-50268","aliases":["GHSA-4j9m-h44m-2hv8"],"url":"https://o3.security/vulnerability/CVE-2026-50268","summary":"Steeltoe: OAEP setting silently selects PKCS#1 v1.5 padding","details":"### Summary\n\nConfiguring `encrypt:rsa:algorithm=OAEP` does not enable OAEP encryption. Due to an incorrect BouncyCastle transformation string, the `OAEP` setting selects PKCS#1 v1.5, which is the same algorithm as the `DEFAULT` setting.\n\n### Impact\n\nOperators who configure `encrypt:rsa:algorithm=OAEP` to obtain CCA2-secure padding receive PKCS#1 v1.5 instead. Currently, `Decrypt()` is called only against operator-controlled configuration data, so no exploitable path exists, but any future code path that exposes a decryption oracle would be Bleichenbacher-vulnerable despite the `OAEP` setting.\n\n### Migration note\n\nExisting `{cipher}` values produced under the broken `OAEP` setting were encrypted with PKCS#1 v1.5. The fix makes `OAEP` use actual OAEP padding, so those values will fail to decrypt after upgrading. Re-encrypt all affected `{cipher}` values after upgrading.","published":"2026-06-17T22:01:19.712Z","modified":"2026-10-21T02:58:25.202857745Z","cvss":{"score":1.9,"severity":"LOW","vector":"CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:N/A:N"},"epss":{"score":0.00047,"percentile":0,"asOf":"2026-09-16"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"NuGet","name":"Steeltoe.Configuration.Encryption","fixedVersion":"4.2.0"}],"fix":{"url":"https://github.com/SteeltoeOSS/Steeltoe/commit/6cfee5cccddf8f9a31de69b0ca5ccdd771b73e5b","label":"SteeltoeOSS/Steeltoe@6cfee5c"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/50xxx/CVE-2026-50268.json"},{"type":"ADVISORY","url":"https://github.com/SteeltoeOSS/security-advisories/security/advisories/GHSA-4j9m-h44m-2hv8"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-50268"},{"type":"FIX","url":"https://github.com/SteeltoeOSS/Steeltoe/commit/6cfee5cccddf8f9a31de69b0ca5ccdd771b73e5b"},{"type":"PACKAGE","url":"https://github.com/SteeltoeOSS/security-advisories"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-10-21T02:58:25.202857745Z"}}