CVE-2020-36203: Reffers Data Races Vulnerability

MODERATE
Advisory Identifier: GHSA-39xg-8p43-h76x
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CVSS 4.7
CWE-362 CWE-787
Published
Advisory Summary

CVE-2020-36203 is a MODERATE (CVSS 4.7) data races vulnerability (CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')) affecting Reffers libraries in the crates.io ecosystem. The issue involves data races in reffers. Remediation is available by upgrading affected packages to version 0.6.1.

CVE-2020-36203 at a Glance

CVE Identifier CVE-2020-36203
GHSA Identifier GHSA-39xg-8p43-h76x
Severity MODERATE
CVSS v3.1 Base Score 4.7
CWE Classification CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
Affected Product Reffers
Package Ecosystem crates.io
Published Date
Last Updated

Security Impact

CVSS: 4.7

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H).

Attack Vector Local (AV:L)
Attack Complexity High (AC:H)
Privileges Required Low (PR:L)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality None (C:N)
Integrity None (I:N)
Availability High (A:H)

How to Fix CVE-2020-36203

To remediate this vulnerability, upgrade all affected Reffers dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

reffers fixed: 0.6.1 
Upgrade reffers to 0.6.1
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

inspect dependencies for reffers

How to Check if You Are Affected

To determine whether your application is affected by CVE-2020-36203, inspect your project dependencies for Reffers:

inspect dependencies for reffers

Analyze the terminal output to locate any version of Reffers in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.6.1), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition'), where the product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently. In Reffers, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

ARefss<'a, V> is a type that is assumed to contain objects that are Send + Sync. In the affected versions of this crate, Send/Sync traits are unconditionally implemented for ARefss<'a, V>. By using the ARefss::map() API, we can insert a !Send or !Sync object into ARefss<'a, V>. After that, it is possible to create a data race to the inner object of ARefss<'a, V>, which can lead to undefined behavior & memory corruption. The flaw was corrected in commit `6dd7ca0` by adding trait bound V: Send + Sync to ARefss::map() API.

CVE-2020-36203 Affected Reffers Versions

1 component(s)
Fixed Versions:
0.6.1
Product / Package Ecosystem Affected Versions Fixed Version
reffers
 crates.io
< 0.6.1
0.6.1

References

NVD — CVE-2020-36203 NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-36203
Reffers Source Repository REPOSITORY
https://github.com/diwic/reffers-rs/issues/7
Security Fix Commit FIX COMMIT
https://github.com/diwic/reffers-rs/commit/6dd7ca0d50f2464df708975cdafcfaeeb6d41c66
Reffers Source Repository REPOSITORY
https://github.com/diwic/reffers-rs
rustsec.org/advisories/rustsec-... WEB
https://rustsec.org/advisories/RUSTSEC-2020-0094.html

Frequently Asked Questions

What is CVE-2020-36203?
CVE-2020-36203 is a security vulnerability in Reffers involving Data races in reffers under CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition').
Which Reffers versions are affected?
Affected versions include releases prior to 0.6.1 across affected packages: reffers.
What version fixes CVE-2020-36203?
Upgrading to 0.6.1 (or the latest patched release for your respective branch) resolves the vulnerability.
Is reffers affected?
Yes, reffers is affected in releases prior to 0.6.1. Upgrade your dependency to 0.6.1 or later.
What is the CVSS score of CVE-2020-36203?
CVE-2020-36203 has a CVSS v3.1 base score of 4.7 (MODERATE) with vector string CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H.
What CWE is associated with CVE-2020-36203?
CVE-2020-36203 is classified under CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') (The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.).
How can I check crates.io dependencies for CVE-2020-36203?
Run the dependency tree command: 'inspect dependencies for reffers'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-39xg-8p43-h76x",
  "modified" : "2023-06-13T20:28:35Z",
  "published" : "2021-08-25T20:51:40Z",
  "aliases" : [ "CVE-2020-36203" ],
  "summary" : "Data races in reffers",
  "details" : "ARefss<'a, V> is a type that is assumed to contain objects that are Send + Sync.\n\nIn the affected versions of this crate, Send/Sync traits are unconditionally implemented for ARefss<'a, V>.\n\nBy using the ARefss::map() API, we can insert a !Send or !Sync object into ARefss<'a, V>. After that, it is possible to create a data race to the inner object of ARefss<'a, V>, which can lead to undefined behavior & memory corruption.\n\nThe flaw was corrected in commit `6dd7ca0` by adding trait bound V: Send + Sync to ARefss::map() API.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "crates.io",
      "name" : "reffers"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "0.6.1"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2020-36203"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/diwic/reffers-rs/issues/7"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/diwic/reffers-rs/commit/6dd7ca0d50f2464df708975cdafcfaeeb6d41c66"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/diwic/reffers-rs"
  }, {
    "type" : "WEB",
    "url" : "https://rustsec.org/advisories/RUSTSEC-2020-0094.html"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-362", "CWE-787" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2021-08-19T18:49:46Z",
    "nvd_published_at" : null
  }
}