Steeltoe Configuration Encryption
Monthly
Steeltoe.Configuration.Encryption 4.0.0 through 4.1.0 silently downgrades RSA encryption from OAEP to PKCS#1 v1.5 when operators explicitly configure `encrypt:rsa:algorithm=OAEP`. The root cause is an incorrect BouncyCastle transformation string in `RsaKeyStoreDecryptor.cs` - the `OAEP` branch passed `"RSA/ECB/PKCS1"` to `CipherUtilities.GetCipher()` instead of the correct `"RSA/NONE/OAEPWithSHA1AndMGF1Padding"`, meaning both the `OAEP` and `DEFAULT` settings silently selected the same weaker algorithm. No public exploit is identified at time of analysis, and CVSS scores this at 1.9 (Low) given the high-privilege local attack vector; however, the security consequence is a cryptographic guarantee failure that exposes encrypted configuration secrets to Bleichenbacher-class padding oracle attacks that OAEP was chosen to prevent.
Steeltoe.Configuration.Encryption 4.0.0 through 4.1.0 silently downgrades RSA encryption from OAEP to PKCS#1 v1.5 when operators explicitly configure `encrypt:rsa:algorithm=OAEP`. The root cause is an incorrect BouncyCastle transformation string in `RsaKeyStoreDecryptor.cs` - the `OAEP` branch passed `"RSA/ECB/PKCS1"` to `CipherUtilities.GetCipher()` instead of the correct `"RSA/NONE/OAEPWithSHA1AndMGF1Padding"`, meaning both the `OAEP` and `DEFAULT` settings silently selected the same weaker algorithm. No public exploit is identified at time of analysis, and CVSS scores this at 1.9 (Low) given the high-privilege local attack vector; however, the security consequence is a cryptographic guarantee failure that exposes encrypted configuration secrets to Bleichenbacher-class padding oracle attacks that OAEP was chosen to prevent.