SecureProps is a PHP library designed to simplify the encryption and decryption of property data in objects. A vulnerability in SecureProps version 1.2.0 and 1.2.1 involves a regex failing to detect tags during decryption of encrypted data. This occurs when the encrypted data has been encoded with `NullEncoder` and passed to `TagAwareCipher`, and contains special characters such as `\n`. As a result, the decryption process is skipped since the tags are not detected. This causes the encrypted data to be returned in plain format. The vulnerability affects users who implement `TagAwareCipher` with any base cipher that has `NullEncoder` (not default). The patch for the issue has been released. Users are advised to update to version 1.2.2. As a workaround, one may use the default `Base64Encoder` with the base cipher decorated with `TagAwareCipher` to prevent special characters in the encrypted string from interfering with regex tag detection logic. This workaround is safe but may involve double encoding since `TagAwareCipher` uses `NullEncoder` by default.