{"id":"CVE-2026-50268","aliases":["EUVD-2026-37821","GHSA-4j9m-h44m-2hv8"],"status":"published","title":"Steeltoe: OAEP setting silently selects PKCS#1 v1.5 padding","description":"Steeltoe is an open source project that provides a collection of libraries that helps users build cloud-native applications. In Steeltoe.Configuration.Encryption 4.0.0 through 4.1.0, configuring `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. Steeltoe.Configuration.Encryption version 4.2.0 patches the issue.","severity":{"version":"3.1","score":1.9,"vector":"CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:N/A:N","level":"low","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00047,"percentile":0.00001,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-256","CWE-327"],"published":"2026-06-17T22:01:19Z","modified":"2026-11-08T10:45:15Z","fixes":[{"ecosystem":"NuGet","package":"Steeltoe.Configuration.Encryption","fixed_in":["4.2.0"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"NuGet","package":"Steeltoe.Configuration.Encryption","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.0.0"},{"last_affected":"4.1.0"},{"fixed":"4.2.0"}]}]},{"source":"osv","ecosystem":"NuGet","package":"Steeltoe.Configuration.Encryption","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.0.0"},{"fixed":"4.2.0"}]}],"versions":["4.0.0","4.1.0"]}],"products":[{"vendor":"steeltoeoss","product":"steeltoe.configuration.encryption"}],"references":[{"url":"https://github.com/SteeltoeOSS/security-advisories/security/advisories/GHSA-4j9m-h44m-2hv8","tags":["x_refsource_CONFIRM","advisory","web"]},{"url":"https://github.com/SteeltoeOSS/Steeltoe/commit/6cfee5cccddf8f9a31de69b0ca5ccdd771b73e5b","tags":["x_refsource_MISC","fix","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-50268","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-4j9m-h44m-2hv8"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/50xxx/CVE-2026-50268.json","tags":["advisory"]},{"url":"https://github.com/SteeltoeOSS/security-advisories","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-50268","title":"Steeltoe: OAEP setting silently selects PKCS#1 v1.5 padding","description":"Steeltoe is an open source project that provides a collection of libraries that helps users build cloud-native applications. In Steeltoe.Configuration.Encryption 4.0.0 through 4.1.0, configuring `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. Steeltoe.Configuration.Encryption version 4.2.0 patches the issue.","status":"published","published":"2026-06-17T22:01:19.712Z","modified":"2026-06-18T13:53:58.47Z","cvss":[{"version":"3.1","score":1.9,"vector":"CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:N/A:N","level":"low","assessor":"cna"}],"cwes":["CWE-256","CWE-327"],"updated_at":"2026-11-02T14:20:08.734143Z"}],"euvd":[{"id":"EUVD-2026-37821","description":"Steeltoe is an open source project that provides a collection of libraries that helps users build cloud-native applications. In Steeltoe.Configuration.Encryption 4.0.0 through 4.1.0, configuring `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. Steeltoe.Configuration.Encryption version 4.2.0 patches the issue.","status":"published","published":"2026-06-17T22:01:19Z","modified":"2026-06-18T13:53:58Z","cvss":[{"version":"3.1","score":1.9,"vector":"CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:N/A:N","level":"low"}],"updated_at":"2026-11-02T18:20:36.672794Z"}],"ghsa":[{"id":"GHSA-4j9m-h44m-2hv8","title":"Steeltoe: OAEP setting silently selects PKCS#1 v1.5 padding","description":"### 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.","status":"published","published":"2026-07-02T20:32:21Z","modified":"2026-07-02T20:32:23Z","cvss":[{"version":"3.1","score":1.9,"vector":"CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:N/A:N","level":"low"}],"cwes":["CWE-256","CWE-327"],"updated_at":"2026-11-02T14:40:38.48196Z"}],"nvd":[{"id":"CVE-2026-50268","description":"Steeltoe is an open source project that provides a collection of libraries that helps users build cloud-native applications. In Steeltoe.Configuration.Encryption 4.0.0 through 4.1.0, configuring `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. Steeltoe.Configuration.Encryption version 4.2.0 patches the issue.","status":"published","published":"2026-06-17T23:17:04.73Z","modified":"2026-10-26T11:10:00.157Z","cvss":[{"version":"3.1","score":1.9,"vector":"CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:N/A:N","level":"low","assessor":"secondary"}],"cwes":["CWE-256","CWE-327"],"updated_at":"2026-11-02T14:12:24.544761Z"}],"osv":[{"id":"CVE-2026-50268","title":"Steeltoe: OAEP setting silently selects PKCS#1 v1.5 padding","description":"Steeltoe is an open source project that provides a collection of libraries that helps users build cloud-native applications. In Steeltoe.Configuration.Encryption 4.0.0 through 4.1.0, configuring `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. Steeltoe.Configuration.Encryption version 4.2.0 patches the issue.","status":"published","published":"2026-06-17T22:01:19.712Z","modified":"2026-11-08T10:45:15.146513096Z","cvss":[{"version":"3.1","score":1.9,"vector":"CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:N/A:N","level":"low"}],"cwes":["CWE-256","CWE-327"],"updated_at":"2026-11-08T11:04:08.386699Z"},{"id":"GHSA-4j9m-h44m-2hv8","title":"Steeltoe: OAEP setting silently selects PKCS#1 v1.5 padding","description":"### 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.","status":"published","published":"2026-07-02T20:32:21Z","modified":"2026-07-02T20:56:33.199322Z","cvss":[{"version":"3.1","score":1.9,"vector":"CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:N/A:N","level":"low"}],"cwes":["CWE-256","CWE-327"],"updated_at":"2026-11-02T15:46:37.148947Z"}]}}