openzeppelin-contracts: Unchecked Return Value
CVE-2022-31170 is a high-severity unchecked return value vulnerability in openzeppelin-contracts from OpenZeppelin, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected openzeppelin-contracts versions: >= 4.0.0, < 4.7.1. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.79% chance of exploitation within 30 days, higher than 57% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Contracts to 4.7.1 or a later version.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| OpenZeppelin | openzeppelin-contracts | >= 4.0.0, < 4.7.1 | Not stated |
| Openzeppelin | Contracts | 4.0.0 up to, but not including, 4.7.1 | 4.7.1 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- HighData or code can be modified at will.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 7.5 | High | CNA (github.com) |
| CVSS 3.1 | 7.5 | High | NVD |
Official description
OpenZeppelin Contracts is a library for smart contract development. Versions 4.0.0 until 4.7.1 are vulnerable to ERC165Checker reverting instead of returning `false`. `ERC165Checker.supportsInterface` is designed to always successfully return a boolean, and under no circumstance revert. However, an incorrect assumption about Solidity 0.8's `abi.decode` allows some cases to revert, given a target contract that doesn't implement EIP-165 as expected, specifically if it returns a value other than 0 or 1. The contracts that may be affected are those that use `ERC165Checker` to check for support for an interface and then handle the lack of support in a way other than reverting. The issue was patched in version 4.7.1.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Unchecked Return Value
The product does not check the return value from a method or function.
How developers prevent this class of flaw
- Check the results of all functions that return a value and verify that the value is expected.
- For any pointers that could have been modified or provided from a function that can return NULL, check the pointer for NULL before use. When working with a multithreaded or otherwise asynchronous environment, ensure that proper locking APIs are used to lock before the check, and unlock when it has finished.
- Ensure that you account for all possible return values from the function.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Advisories
Patches and release notes
- github.com/OpenZeppelin/openzeppelin-contracts/pull/3552Third Party Advisory
Other vulnerabilities in openzeppelin-contracts
- 7.4 High severity
- 7.5 High severity
- 8.8 High severity
- 7.5 High severity
- 7.5 High severity
Recent Unchecked Return Value vulnerabilities
- 7.5 High severity
- 7.5 High severity
- 9.1 Critical severity
- 8.8 High severity
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