RUSTSEC-2020-0068

Unexpected panic in multihash from_slice parsing code

Reported

November 8, 2020

Issued

November 9, 2020 (last modified: June 13, 2023)

Package

multihash (crates.io)

Type

Vulnerability

Categories

denial-of-service

Keywords

#parsing #panic #untrusted-data

Aliases

References

https://github.com/multiformats/rust-multihash/pull/72

CVSS Score

7.5 HIGH

CVSS Details

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

CVSS Vector

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

Patched

>=0.11.3

Affected Functions

Version

multihash::digests::MultihashGeneric::from_bytes

<0.11.3

multihash::digests::MultihashRefGeneric::from_slice

<0.11.3

Description

In versions prior 0.11.3 it's possible to make from_slice panic by feeding it certain malformed input. It's never documented that from_slice (and from_bytes which wraps it) can panic, and its' return type (Result<Self, DecodeError>) suggests otherwise.

In practice, from_slice/from_bytes is frequently used in networking code (for example in rust-libp2p) and is being called with unsanitized data from untrusted sources. This can allow attackers to cause DoS by causing an unexpected panic in the network client's code.

Advisory available under CC0-1.0 license.