Описание
OpenZeppelin Contracts base64 encoding may read from potentially dirty memory
Impact
The Base64.encode function encodes a bytes input by iterating over it in chunks of 3 bytes. When this input is not a multiple of 3, the last iteration may read parts of the memory that are beyond the input buffer.
Although the encode function pads the output for these cases, up to 4 bits of data are kept between the encoding and padding, corrupting the output if these bits were dirty (i.e. memory after the input is not 0). These conditions are more frequent in the following scenarios:
- A
bytes memorystruct is allocated just after the input and the first bytes of it are non-zero. - The memory pointer is set to a non-empty memory location before allocating the input.
Developers should evaluate whether the extra bits can be maliciously manipulated by an attacker.
Patches
Upgrade to 5.0.2 or 4.9.6.
References
This issue was reported by the Independent Security Researcher Riley Holterhus through Immunefi (@rileyholterhus on X)
Ссылки
- https://github.com/OpenZeppelin/openzeppelin-contracts/security/advisories/GHSA-9vx6-7xxf-x967
- https://nvd.nist.gov/vuln/detail/CVE-2024-27094
- https://github.com/OpenZeppelin/openzeppelin-contracts-upgradeable/commit/2d081f24cac1a867f6f73d512f2022e1fa987854
- https://github.com/OpenZeppelin/openzeppelin-contracts-upgradeable/commit/723f8cab09cdae1aca9ec9cc1cfa040c2d4b06c1
- https://github.com/OpenZeppelin/openzeppelin-contracts/commit/92224533b1263772b0774eec3134e132a3d7b2a6
- https://github.com/OpenZeppelin/openzeppelin-contracts/commit/a6286d0fded8771b3a645e5813e51993c490399c
Пакеты
@openzeppelin/contracts
>= 4.5.0, < 4.9.6
4.9.6
@openzeppelin/contracts-upgradeable
>= 5.0.0-rc.0, < 5.0.2
5.0.2
@openzeppelin/contracts
>= 5.0.0-rc.0, < 5.0.2
5.0.2
@openzeppelin/contracts-upgradeable
>= 4.5.0, < 4.9.6
4.9.6
Связанные уязвимости
OpenZeppelin Contracts is a library for secure smart contract development. The `Base64.encode` function encodes a `bytes` input by iterating over it in chunks of 3 bytes. When this input is not a multiple of 3, the last iteration may read parts of the memory that are beyond the input buffer. The vulnerability is fixed in 5.0.2 and 4.9.6.