CVE-2020-36434: Sys info Double Free Vulnerability

CRITICAL
Advisory Identifier: GHSA-2f5j-3mhq-xv58
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CVSS 9.8
CWE-415
Published
Advisory Summary

CVE-2020-36434 is a CRITICAL (CVSS 9.8) double free vulnerability (CWE-415: Double Free) affecting Sys info libraries in the crates.io ecosystem. The issue involves double free in sys-info. Remediation is available by upgrading affected packages to version 0.8.0.

CVE-2020-36434 at a Glance

CVE Identifier CVE-2020-36434
GHSA Identifier GHSA-2f5j-3mhq-xv58
Severity CRITICAL
CVSS v3.1 Base Score 9.8
CWE Classification CWE-415: Double Free
Affected Product Sys info
Package Ecosystem crates.io
Published Date
Last Updated

Security Impact

CVSS: 9.8

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

How to Fix CVE-2020-36434

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

sys-info fixed: 0.8.0 
Upgrade sys-info to 0.8.0
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 sys-info

How to Check if You Are Affected

To determine whether your application is affected by CVE-2020-36434, inspect your project dependencies for Sys info:

inspect dependencies for sys-info

Analyze the terminal output to locate any version of Sys info in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.8.0), 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-415: Double Free, where the product calls free() twice on the same memory address. In Sys info, 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

Affected versions of sys-info use a static, global, list to store temporary disk information while running. The function that cleans up this list, DFCleanup, assumes a single threaded environment and will try to free the same memory twice in a multithreaded environment. This results in consistent double-frees and segfaults when calling sys_info::disk_info from multiple threads at once. The issue was fixed by moving the global variable into a local scope.

CVE-2020-36434 Affected Sys info Versions

1 component(s)
Fixed Versions:
0.8.0
Product / Package Ecosystem Affected Versions Fixed Version
sys-info
 crates.io
< 0.8.0
0.8.0

References

NVD — CVE-2020-36434 NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-36434
Sys info Source Repository REPOSITORY
https://github.com/FillZpp/sys-info-rs/issues/63
Sys info Source Repository REPOSITORY
https://github.com/FillZpp/sys-info-rs
raw.githubusercontent.com/rustsec/advisory-db... WEB
https://raw.githubusercontent.com/rustsec/advisory-db/main/crates/sys-info/RUSTSEC-2020-0100.md
rustsec.org/advisories/rustsec-... WEB
https://rustsec.org/advisories/RUSTSEC-2020-0100.html

Frequently Asked Questions

What is CVE-2020-36434?
CVE-2020-36434 is a security vulnerability in Sys info involving Double free in sys-info under CWE-415: Double Free.
Which Sys info versions are affected?
Affected versions include releases prior to 0.8.0 across affected packages: sys-info.
What version fixes CVE-2020-36434?
Upgrading to 0.8.0 (or the latest patched release for your respective branch) resolves the vulnerability.
Is sys-info affected?
Yes, sys-info is affected in releases prior to 0.8.0. Upgrade your dependency to 0.8.0 or later.
What is the CVSS score of CVE-2020-36434?
CVE-2020-36434 has a CVSS v3.1 base score of 9.8 (CRITICAL) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
What CWE is associated with CVE-2020-36434?
CVE-2020-36434 is classified under CWE-415: Double Free (The product calls free() twice on the same memory address.).
How can I check crates.io dependencies for CVE-2020-36434?
Run the dependency tree command: 'inspect dependencies for sys-info'. 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-2f5j-3mhq-xv58",
  "modified" : "2023-06-13T22:04:49Z",
  "published" : "2021-08-25T20:58:15Z",
  "aliases" : [ "CVE-2020-36434" ],
  "summary" : "Double free in sys-info ",
  "details" : "Affected versions of sys-info use a static, global, list to store temporary disk information while running. The function that cleans up this list, DFCleanup, assumes a single threaded environment and will try to free the same memory twice in a multithreaded environment. This results in consistent double-frees and segfaults when calling sys_info::disk_info from multiple threads at once. The issue was fixed by moving the global variable into a local scope.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "crates.io",
      "name" : "sys-info"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "0.8.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2020-36434"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/FillZpp/sys-info-rs/issues/63"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/FillZpp/sys-info-rs"
  }, {
    "type" : "WEB",
    "url" : "https://raw.githubusercontent.com/rustsec/advisory-db/main/crates/sys-info/RUSTSEC-2020-0100.md"
  }, {
    "type" : "WEB",
    "url" : "https://rustsec.org/advisories/RUSTSEC-2020-0100.html"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-415" ],
    "severity" : "CRITICAL",
    "github_reviewed" : true,
    "github_reviewed_at" : "2021-08-18T20:16:40Z",
    "nvd_published_at" : "2021-08-08T06:15:00Z"
  }
}