CVE-2023-46234

browserify-sign is a package to duplicate the functionality of node's crypto public key functions, much of this is based on Fedor Indutny's work on indutny/tls.js. An upper bound check issue in dsaVerify function allows an attacker to construct signatures that can be successfully verified by any public key, thus leading to a signature forgery attack. All places in this project that involve DSA verification of user-input signatures will be affected by this vulnerability. This issue has been patched in version 4.2.2.

browserify-sign is a package to duplicate the functionality of node's crypto public key functions, much of this is based on Fedor Indutny's work on indutny/tls.js. An upper bound check issue in dsaVerify function allows an attacker to construct signatures that can be successfully verified by any public key, thus leading to a signature forgery attack. All places in this project that involve DSA verification of user-input signatures will be affected by this vulnerability. This issue has been patched in version 4.2.2.

Summary

An upper bound check issue in dsaVerify function allows an attacker to construct signatures that can be successfully verified by any public key, thus leading to a signature forgery attack.

Details

In dsaVerify function, it checks whether the value of the signature is legal by calling function checkValue, namely, whether r and s are both in the interval [1, q - 1]. However, the second line of the checkValue function wrongly checks the upper bound of the passed parameters, since the value of b.cmp(q) can only be 0, 1 and -1, and it can never be greater than q.

In this way, although the values of s cannot be 0, an attacker can achieve the same effect as zero by setting its value to q, and then send (r, s) = (1, q) to pass the verification of any public key.

Impact

All places in this project that involve DSA verification of user-input signatures will be affected by this vulnerability.

Fix PR:

Since the temporary private fork was deleted, here's a webarchive of the PR discussion and diff pages: PR webarchive.zip

browserify-sign is a package to duplicate the functionality of node's crypto public key functions, much of this is based on Fedor Indutny's work on indutny/tls.js. An upper bound check issue in dsaVerify function allows an attacker to construct signatures that can be successfully verified by any public key, thus leading to a signature forgery attack. All places in this project that involve DSA verification of user-input signatures will be affected by this vulnerability. This issue has been patched in version 4.2.2.

browserify-sign is a package to duplicate the functionality of node's crypto public key functions, much of this is based on Fedor Indutny's work on indutny/tls.js. An upper bound check issue in dsaVerify function allows an attacker to construct signatures that can be successfully verified by any public key, thus leading to a signature forgery attack. All places in this project that involve DSA verification of user-input signatures will be affected by this vulnerability. This issue has been patched in version 4.2.2.

browserify-sign is a package to duplicate the functionality of node's crypto public key functions, much of this is based on Fedor Indutny's work on indutny/tls.js. An upper bound check issue in dsaVerify function allows an attacker to construct signatures that can be successfully verified by any public key, thus leading to a signature forgery attack. All places in this project that involve DSA verification of user-input signatures will be affected by this vulnerability. This issue has been patched in version 4.2.2.