CVE-2023-34459 – @openzeppelin/contracts-upgradeable

Package

Manager: npm
Name: @openzeppelin/contracts-upgradeable
Vulnerable Version: >=4.7.0 <4.9.2

Severity

Level: Medium

CVSS v3.1: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:N

CVSS v4.0: CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

EPSS: 0.00632 pctl0.69443

Details

OpenZeppelin Contracts using MerkleProof multiproofs may allow proving arbitrary leaves for specific trees ### Impact When the `verifyMultiProof`, `verifyMultiProofCalldata`, `processMultiProof`, or `processMultiProofCalldata` functions are in use, it is possible to construct merkle trees that allow forging a valid multiproof for an arbitrary set of leaves. A contract may be vulnerable if it uses multiproofs for verification and the merkle tree that is processed includes a node with value 0 at depth 1 (just under the root). This could happen inadvertently for balanced trees with 3 leaves or less, if the leaves are not hashed. This could happen deliberately if a malicious tree builder includes such a node in the tree. A contract is not vulnerable if it uses single-leaf proving (`verify`, `verifyCalldata`, `processProof`, or `processProofCalldata`), or if it uses multiproofs with a known tree that has hashed leaves. Standard merkle trees produced or validated with the [@openzeppelin/merkle-tree](https://github.com/OpenZeppelin/merkle-tree) library are safe. ### Patches The problem has been patched in 4.9.2. ### Workarounds If you are using multiproofs: When constructing merkle trees hash the leaves and do not insert empty nodes in your trees. Using the [@openzeppelin/merkle-tree](https://www.npmjs.com/package/@openzeppelin/merkle-tree) package eliminates this issue. Do not accept user-provided merkle roots without reconstructing at least the first level of the tree. Verify the merkle tree structure by reconstructing it from the leaves.

Metadata

Created: 2023-06-19T19:46:37Z
Modified: 2023-06-19T19:46:37Z
Source: https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2023/06/GHSA-wprv-93r4-jj2p/GHSA-wprv-93r4-jj2p.json
CWE IDs: ["CWE-354"]
Alternative ID: GHSA-wprv-93r4-jj2p
Finding: F086
Auto approve: 1