CVE-2018-20989: Untrusted Integer Underflow Vulnerability

HIGH
Advisory Identifier: GHSA-wq8f-46ww-6c2h
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CVSS 7.5
CWE-191
Published
Advisory Summary

CVE-2018-20989 is a HIGH (CVSS 7.5) integer underflow vulnerability (CWE-191: Integer Underflow (Wrap or Wraparound)) affecting Untrusted libraries in the crates.io ecosystem. The issue involves integer underflow in untrusted. Remediation is available by upgrading affected packages to version 0.6.2.

CVE-2018-20989 at a Glance

CVE Identifier CVE-2018-20989
GHSA Identifier GHSA-wq8f-46ww-6c2h
Severity HIGH
CVSS v3.1 Base Score 7.5
CWE Classification CWE-191: Integer Underflow (Wrap or Wraparound)
Affected Product Untrusted
Package Ecosystem crates.io
Published Date
Last Updated

Security Impact

CVSS: 7.5

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
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-2018-20989

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

untrusted fixed: 0.6.2 
Upgrade untrusted to 0.6.2
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 untrusted

How to Check if You Are Affected

To determine whether your application is affected by CVE-2018-20989, inspect your project dependencies for Untrusted:

inspect dependencies for untrusted

Analyze the terminal output to locate any version of Untrusted in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.6.2), 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-191: Integer Underflow (Wrap or Wraparound), where the product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result. In Untrusted, 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

A mistake in error handling in untrusted before 0.6.2 could lead to an integer underflow and panic if a user of the crate didn't properly check for errors returned by untrusted. Combination of these two programming errors (one in untrusted and another by user of this crate) could lead to a panic and maybe a denial of service of affected software. The error in untrusted is fixed in release 0.6.2 released 2018-06-21. It's also advisable that users of untrusted check for their sources for cases where errors returned by untrusted are not handled correctly.

CVE-2018-20989 Affected Untrusted Versions

1 component(s)
Fixed Versions:
0.6.2
Product / Package Ecosystem Affected Versions Fixed Version
untrusted
 crates.io
< 0.6.2
0.6.2

References

NVD — CVE-2018-20989 NVD
https://nvd.nist.gov/vuln/detail/CVE-2018-20989
Untrusted Source Repository REPOSITORY
https://github.com/briansmith/untrusted/pull/20
Untrusted Source Repository REPOSITORY
https://github.com/briansmith/untrusted
rustsec.org/advisories/rustsec-... WEB
https://rustsec.org/advisories/RUSTSEC-2018-0001.html

Frequently Asked Questions

What is CVE-2018-20989?
CVE-2018-20989 is a security vulnerability in Untrusted involving Integer underflow in untrusted under CWE-191: Integer Underflow (Wrap or Wraparound).
Which Untrusted versions are affected?
Affected versions include releases prior to 0.6.2 across affected packages: untrusted.
What version fixes CVE-2018-20989?
Upgrading to 0.6.2 (or the latest patched release for your respective branch) resolves the vulnerability.
Is untrusted affected?
Yes, untrusted is affected in releases prior to 0.6.2. Upgrade your dependency to 0.6.2 or later.
What is the CVSS score of CVE-2018-20989?
CVE-2018-20989 has a CVSS v3.1 base score of 7.5 (HIGH) with vector string CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
What CWE is associated with CVE-2018-20989?
CVE-2018-20989 is classified under CWE-191: Integer Underflow (Wrap or Wraparound) (The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result.).
How can I check crates.io dependencies for CVE-2018-20989?
Run the dependency tree command: 'inspect dependencies for untrusted'. 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-wq8f-46ww-6c2h",
  "modified" : "2023-06-13T22:27:01Z",
  "published" : "2021-08-25T20:43:49Z",
  "aliases" : [ "CVE-2018-20989" ],
  "summary" : "Integer underflow in untrusted",
  "details" : "A mistake in error handling in untrusted before 0.6.2 could lead to an integer underflow and panic if a user of the crate didn't properly check for errors returned by untrusted. Combination of these two programming errors (one in untrusted and another by user of this crate) could lead to a panic and maybe a denial of service of affected software. The error in untrusted is fixed in release 0.6.2 released 2018-06-21. It's also advisable that users of untrusted check for their sources for cases where errors returned by untrusted are not handled correctly.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "crates.io",
      "name" : "untrusted"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "0.6.2"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2018-20989"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/briansmith/untrusted/pull/20"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/briansmith/untrusted"
  }, {
    "type" : "WEB",
    "url" : "https://rustsec.org/advisories/RUSTSEC-2018-0001.html"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-191" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2021-08-19T21:24:20Z",
    "nvd_published_at" : null
  }
}