Vulnerabilities > CVE-2022-29173 - Improper Validation of Integrity Check Value vulnerability in Theupdateframework Go-Tuf 0.2.0
Summary
go-tuf is a Go implementation of The Update Framework (TUF). go-tuf does not correctly implement the client workflow for updating the metadata files for roles other than the root role. Specifically, checks for rollback attacks are not implemented correctly meaning an attacker can cause clients to install software that is older than the software which the client previously knew to be available, and may include software with known vulnerabilities. In more detail, the client code of go-tuf has several issues in regards to preventing rollback attacks: 1. It does not take into account the content of any previously trusted metadata, if available, before proceeding with updating roles other than the root role (i.e., steps 5.4.3.1 and 5.5.5 of the detailed client workflow). This means that any form of version verification done on the newly-downloaded metadata is made using the default value of zero, which always passes. 2. For both timestamp and snapshot roles, go-tuf saves these metadata files as trusted before verifying if the version of the metafiles they refer to is correct (i.e., steps 5.5.4 and 5.6.4 of the detailed client workflow). A fix is available in version 0.3.0 or newer. No workarounds are known for this issue apart from upgrading.
Vulnerable Configurations
| Part | Description | Count |
|---|---|---|
| Application | 1 |
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Padding Oracle Crypto Attack An attacker is able to efficiently decrypt data without knowing the decryption key if a target system leaks data on whether or not a padding error happened while decrypting the ciphertext. A target system that leaks this type of information becomes the padding oracle and an attacker is able to make use of that oracle to efficiently decrypt data without knowing the decryption key by issuing on average 128*b calls to the padding oracle (where b is the number of bytes in the ciphertext block). In addition to performing decryption, an attacker is also able to produce valid ciphertexts (i.e., perform encryption) by using the padding oracle, all without knowing the encryption key. Any cryptosystem can be vulnerable to padding oracle attacks if the encrypted messages are not authenticated to ensure their validity prior to decryption, and then the information about padding error is leaked to the attacker. This attack technique may be used, for instance, to break CAPTCHA systems or decrypt/modify state information stored in client side objects (e.g., hidden fields or cookies). This attack technique is a side-channel attack on the cryptosystem that uses a data leak from an improperly implemented decryption routine to completely subvert the cryptosystem. The one bit of information that tells the attacker whether a padding error during decryption has occurred, in whatever form it comes, is sufficient for the attacker to break the cryptosystem. That bit of information can come in a form of an explicit error message about a padding error, a returned blank page, or even the server taking longer to respond (a timing attack). This attack can be launched cross domain where an attacker is able to use cross-domain information leaks to get the bits of information from the padding oracle from a target system / service with which the victim is communicating. To do so an attacker sends a request containing ciphertext to the target system. Due to the browser's same origin policy, the attacker is not able to see the response directly, but can use cross-domain information leak techniques to still get the information needed (i.e., information on whether or not a padding error has occurred). For instance, this can be done using "img" tag plus the onerror()/onload() events. The attacker's JavaScript can make web browsers to load an image on the target site, and know if the image is loaded or not. This is 1-bit information needed for the padding oracle attack to work: if the image is loaded, then it is valid padding, otherwise it is not.
- Manipulating Writeable Configuration Files Generally these are manually edited files that are not in the preview of the system administrators, any ability on the attackers' behalf to modify these files, for example in a CVS repository, gives unauthorized access directly to the application, the same as authorized users.