CVE-2020-35923: ordered_float NotNan May Contain NaN After Vulnerability

MODERATE
Advisory Identifier: GHSA-566x-hhrf-qf8m
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CVSS 5.5
CWE-460
Published
Advisory Summary

CVE-2020-35923 is a MODERATE (CVSS 5.5) notnan may contain nan after vulnerability (CWE-460: Improper Cleanup on Thrown Exception) affecting ordered_float libraries in the crates.io ecosystem. The issue involves notnan may contain nan after panic in assignment operators. Remediation is available by upgrading affected packages to version 2.0.1, 1.1.1.

CVE-2020-35923 at a Glance

CVE Identifier CVE-2020-35923
GHSA Identifier GHSA-566x-hhrf-qf8m
Severity MODERATE
CVSS v3.1 Base Score 5.5
CWE Classification CWE-460: Improper Cleanup on Thrown Exception
Affected Product ordered_float
Package Ecosystem crates.io
Published Date
Last Updated

Security Impact

CVSS: 5.5

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

Attack Vector Local (AV:L)
Attack Complexity Low (AC:L)
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-2020-35923

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

ordered-float fixed: 2.0.1 
Upgrade ordered-float to 2.0.1
ordered-float fixed: 1.1.1 
Upgrade ordered-float to 1.1.1
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 ordered-float

How to Check if You Are Affected

To determine whether your application is affected by CVE-2020-35923, inspect your project dependencies for ordered_float:

inspect dependencies for ordered-float

Analyze the terminal output to locate any version of ordered_float in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2.0.1), 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-460: Improper Cleanup on Thrown Exception, where the product does not clean up its state or incorrectly cleans up its state when an exception is thrown, leading to unexpected state or control flow. In ordered_float, 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

After using an assignment operators such as NotNan::add_assign, NotNan::mul_assign, etc., it was possible for the resulting NotNan value to contain a NaN. This could cause undefined behavior in safe code, because the safe NotNan::cmp method contains internal unsafe code that assumes the value is never NaN. (It could also cause undefined behavior in third-party unsafe code that makes the same assumption, as well as logic errors in safe code.) This was mitigated starting in version 0.4.0, by panicking if the assigned value is NaN. However, in affected versions from 0.4.0 onward, code that uses the NotNan value during unwinding, or that continues after catching the panic, could still observe the invalid value and trigger undefined behavior. The flaw is fully corrected in versions 1.1.1 and 2.0.1, by ensuring that the assignment operators panic without modifying the operand, if the result would be NaN.

CVE-2020-35923 Affected ordered_float Versions

2 component(s)
Fixed Versions:
2.0.11.1.1
Product / Package Ecosystem Affected Versions Fixed Version
ordered-float
 crates.io
≥ 2.0.0
< 2.0.1
All 1 versions
2.0.0
2.0.1
ordered-float
 crates.io
≥ 0.2.2
< 1.1.1
1.1.1

References

NVD — CVE-2020-35923 NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-35923
ordered_float Source Repository REPOSITORY
https://github.com/reem/rust-ordered-float/pull/71
Security Fix Commit FIX COMMIT
https://github.com/reem/rust-ordered-float/commit/c55cda301c943270b7eb2b4765bedbcce56edb90
Security Fix Commit FIX COMMIT
https://github.com/reem/rust-ordered-float/commit/da4a8dd49300740a434c095a9c4b408d2415cc08
ordered_float Source Repository REPOSITORY
https://github.com/reem/rust-ordered-float
rustsec.org/advisories/rustsec-... WEB
https://rustsec.org/advisories/RUSTSEC-2020-0082.html

Frequently Asked Questions

What is CVE-2020-35923?
CVE-2020-35923 is a security vulnerability in ordered_float involving NotNan may contain NaN after panic in assignment operators under CWE-460: Improper Cleanup on Thrown Exception.
Which ordered_float versions are affected?
Affected versions include releases prior to 2.0.1, 1.1.1 across affected packages: ordered-float.
What version fixes CVE-2020-35923?
Upgrading to 2.0.1, 1.1.1 (or the latest patched release for your respective branch) resolves the vulnerability.
Is ordered-float affected?
Yes, ordered-float is affected in releases prior to 2.0.1, 1.1.1. Upgrade your dependency to 2.0.1, 1.1.1 or later.
What is the CVSS score of CVE-2020-35923?
CVE-2020-35923 has a CVSS v3.1 base score of 5.5 (MODERATE) with vector string CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.
What CWE is associated with CVE-2020-35923?
CVE-2020-35923 is classified under CWE-460: Improper Cleanup on Thrown Exception (The product does not clean up its state or incorrectly cleans up its state when an exception is thrown, leading to unexpected state or control flow.).
How can I check crates.io dependencies for CVE-2020-35923?
Run the dependency tree command: 'inspect dependencies for ordered-float'. 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-566x-hhrf-qf8m",
  "modified" : "2023-06-13T19:51:43Z",
  "published" : "2021-08-25T20:50:30Z",
  "aliases" : [ "CVE-2020-35923" ],
  "summary" : "ordered_float:NotNan may contain NaN after panic in assignment operators",
  "details" : "After using an assignment operators such as NotNan::add_assign, NotNan::mul_assign, etc., it was possible for the resulting NotNan value to contain a NaN. This could cause undefined behavior in safe code, because the safe NotNan::cmp method contains internal unsafe code that assumes the value is never NaN. (It could also cause undefined behavior in third-party unsafe code that makes the same assumption, as well as logic errors in safe code.)\n\nThis was mitigated starting in version 0.4.0, by panicking if the assigned value is NaN. However, in affected versions from 0.4.0 onward, code that uses the NotNan value during unwinding, or that continues after catching the panic, could still observe the invalid value and trigger undefined behavior.\n\nThe flaw is fully corrected in versions 1.1.1 and 2.0.1, by ensuring that the assignment operators panic without modifying the operand, if the result would be NaN.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "crates.io",
      "name" : "ordered-float"
    },
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  "references" : [ {
    "type" : "ADVISORY",
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  }, {
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    "url" : "https://github.com/reem/rust-ordered-float/pull/71"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/reem/rust-ordered-float/commit/c55cda301c943270b7eb2b4765bedbcce56edb90"
  }, {
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  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/reem/rust-ordered-float"
  }, {
    "type" : "WEB",
    "url" : "https://rustsec.org/advisories/RUSTSEC-2020-0082.html"
  } ],
  "database_specific" : {
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    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2021-08-19T18:54:34Z",
    "nvd_published_at" : null
  }
}