RUSTSEC-2021-0122

Generated code can read and write out of bounds in safe code

Reported

October 31, 2021

Issued

November 7, 2021 (last modified: October 18, 2022)

Package

flatbuffers (crates.io)

Type

Vulnerability

Details

https://github.com/google/flatbuffers/issues/6627

CVSS Score

9.8 CRITICAL

CVSS Details

Attack vector: Network
Attack complexity: Low
Privileges required: None
User interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: High
Availability: High

CVSS Vector

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

Patched

>=22.9.29

Description

Code generated by flatbuffers' compiler is unsafe but not marked as such. See https://github.com/google/flatbuffers/issues/6627 for details.

For example, if generated code is used to decode malformed or untrusted input, undefined behavior (and thus security vulnerabilities) is possible even without the use of the unsafe keyword, violating the the meaning of "safe" code;

All users that use generated code by flatbuffers compiler are recommended to:

not expose flatbuffer generated code as part of their public APIs
audit their code and look for any usage of follow, push, or any method that uses them (e.g. self_follow).
Carefuly go through the crates' documentation to understand which "safe" APIs are not intended to be used.