Skip to content

Binary vulnerable to Slice Memory Allocation with Excessive Size Value

High severity GitHub Reviewed Published Sep 1, 2022 in gagliardetto/binary • Updated Feb 9, 2023

Package

gomod github.com/gagliardetto/binary (Go)

Affected versions

< 0.7.1

Patched versions

0.7.1

Description

Impact

What kind of vulnerability is it? Who is impacted?

The vulnerability is a memory allocation vulnerability that can be exploited to allocate slices in memory with (arbitrary) excessive size value, which can either exhaust available memory or crash the whole program.

When using github.com/gagliardetto/binary to parse unchecked (or wrong type of) data from untrusted sources of input (e.g. the blockchain) into slices, it's possible to allocate memory with excessive size.

When dec.Decode(&val) method is used to parse data into a structure that is or contains slices of values, the length of the slice was previously read directly from the data itself without any checks on the size of it, and then a slice was allocated. This could lead to an overflow and an allocation of memory with excessive size value.

Example:

package main

import (
	"github.com/gagliardetto/binary" // any version before v0.7.1 is vulnerable
	"log"
)

type MyStruct struct {
	Field1 []byte // field is a slice (could be a slice of any type)
}

func main() {
	// Let's assume that the data is coming from the blockchain:
	data := []byte{0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10}
	
	var val MyStruct
	// - To determine the size of the val.Field1 slice, the decoder will read the length
	//   of the slice from the data itself without any checks on the size of it.
	//
	// - This could lead to an allocation of memory with excessive size value.
	//   Which means: []byte{0x01, 0x02, 0x03, 0x04} will be read as the length
	//   of the slice (= 67305985) and then an allocation of memory with 67305985 bytes will be made.
	//
	dec := binary.NewBorshDecoder(data)
	err := dec.Decode(&val)  // or binary.UnmarshalBorsh(&val, data) or binary.UnmarshalBin(&val, data) etc.
	if err != nil {
		log.Fatal(err)
	}
}

Patches

Has the problem been patched? What versions should users upgrade to?

The vulnerability has been patched in github.com/gagliardetto/binary v0.7.1

Users should upgrade to v0.7.1 or higher.

To upgrade to v0.7.1 or higher, run:

go get github.com/gagliardetto/binary@v0.7.1

# or

go get github.com/gagliardetto/binary@latest

Workarounds

Is there a way for users to fix or remediate the vulnerability without upgrading?

A workaround is not to rely on the dec.Decode(&val) function to parse the data, but to use a custom UnmarshalWithDecoder() method that reads and checks the length of any slice.

References

Are there any links users can visit to find out more?

For more information

If you have any questions or comments about this advisory:

References

@gagliardetto gagliardetto published to gagliardetto/binary Sep 1, 2022
Published by the National Vulnerability Database Sep 2, 2022
Published to the GitHub Advisory Database Sep 16, 2022
Reviewed Sep 16, 2022
Last updated Feb 9, 2023

Severity

High

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v3 base metrics

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

CVSS v3 base metrics

Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

EPSS score

0.172%
(55th percentile)

CVE ID

CVE-2022-36078

GHSA ID

GHSA-4p6f-m4f9-ch88

Source code

Loading Checking history
See something to contribute? Suggest improvements for this vulnerability.