An issue was discovered in heinekingmedia StashCat through 1.7.5 for Android. The keystore is locked with a hard-coded password. Therefore, everyone with access to the keystore can read the content out, for example the private key of the user.

An issue was discovered in heinekingmedia StashCat through 1.7.5 for Android, through 0.0.80w for Web, and through 0.0.86 for Desktop. The product's protocol only tries to ensure confidentiality. In the whole protocol, no integrity or authenticity checks are done. Therefore man-in-the-middle attackers can conduct replay attacks.

An issue was discovered in heinekingmedia StashCat through 1.7.5 for Android, through 0.0.80w for Web, and through 0.0.86 for Desktop. For authentication, the user password is hashed directly with SHA-512 without a salt or another key-derivation mechanism to enable a secure secret for authentication. Moreover, only the first 32 bytes of the hash are used. This allows for easy dictionary and rainbow-table attacks if an attacker has access to the password hash.

An issue was discovered in heinekingmedia StashCat through 1.7.5 for Android, through 0.0.80w for Web, and through 0.0.86 for Desktop. To encrypt messages, AES in CBC mode is used with a pseudo-random secret. This secret and the IV are generated with math.random() in previous versions and with CryptoJS.lib.WordArray.random() in newer versions, which uses math.random() internally. This is not cryptographically strong.

An issue was discovered in heinekingmedia StashCat through 1.7.5 for Android. The login credentials are written into a log file on the device. Hence, an attacker with access to the logs can read them.

An issue was discovered in heinekingmedia StashCat through 1.7.5 for Android, through 0.0.80w for Web, and through 0.0.86 for Desktop. The logout mechanism does not check for authorization. Therefore, an attacker only needs to know the device ID. This causes a denial of service. This might be interpreted as a vulnerability in customer-controlled software, in the sense that the StashCat client side has no secure way to signal that it is ending a session and that data should be deleted.

An issue was discovered in heinekingmedia StashCat through 1.7.5 for Android, through 0.0.80w for Web, and through 0.0.86 for Desktop. It uses RSA to exchange a secret for symmetric encryption of messages. However, the private RSA key is not only stored on the client but transmitted to the backend, too. Moreover, the key to decrypt the private key is composed of the first 32 bytes of the SHA-512 hash of the user password. But this hash is stored on the backend, too. Therefore, everyone with access to the backend database can read the transmitted secret for symmetric encryption, hence can read the communication.