CVE-2021-45701: Tremor script Use After Free Vulnerability

CRITICAL
Advisory Identifier: GHSA-q2x5-6q7q-r872
CVSS 9.8
CWE-416
Published
Advisory Summary

CVE-2021-45701 is a CRITICAL (CVSS 9.8) use after free vulnerability (CWE-416: Use After Free) affecting Tremor script libraries in the crates.io ecosystem. The issue involves use after free in tremor-script. Remediation is available by upgrading affected packages to version 0.11.6.

CVE-2021-45701 at a Glance

CVE Identifier CVE-2021-45701
GHSA Identifier GHSA-q2x5-6q7q-r872
Severity CRITICAL
CVSS v3.1 Base Score 9.8
CWE Classification CWE-416: Use After Free
Affected Product Tremor script
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-2021-45701

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

tremor-script fixed: 0.11.6
Upgrade tremor-script to 0.11.6
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 tremor-script

How to Check if You Are Affected

To determine whether your application is affected by CVE-2021-45701, inspect your project dependencies for Tremor script:

inspect dependencies for tremor-script

Analyze the terminal output to locate any version of Tremor script in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.11.6), 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-416: Use After Free, where the product reuses or references memory after it has been freed. at some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer. In Tremor script, 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

An issue was discovered in the tremor-script crate before 0.11.6 for Rust. A patch operation may result in a use-after-free.

CVE-2021-45701 Affected Tremor script Versions

1 component(s)
Fixed Versions:
0.11.6
Product / Package Ecosystem Affected Versions Fixed Version
tremor-script
crates.io
≥ 0.7.2
< 0.11.6
0.11.6

References

Frequently Asked Questions

What is CVE-2021-45701?
CVE-2021-45701 is a security vulnerability in Tremor script involving Use After Free in tremor-script under CWE-416: Use After Free.
Which Tremor script versions are affected?
Affected versions include releases prior to 0.11.6 across affected packages: tremor-script.
What version fixes CVE-2021-45701?
Upgrading to 0.11.6 (or the latest patched release for your respective branch) resolves the vulnerability.
Is tremor-script affected?
Yes, tremor-script is affected in releases prior to 0.11.6. Upgrade your dependency to 0.11.6 or later.
What is the CVSS score of CVE-2021-45701?
CVE-2021-45701 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-2021-45701?
CVE-2021-45701 is classified under CWE-416: Use After Free (The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.).
How can I check crates.io dependencies for CVE-2021-45701?
Run the dependency tree command: 'inspect dependencies for tremor-script'. 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
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-q2x5-6q7q-r872",
  "modified" : "2022-01-07T17:52:38Z",
  "published" : "2022-01-06T22:10:17Z",
  "aliases" : [ "CVE-2021-45701" ],
  "summary" : "Use After Free in tremor-script",
  "details" : "An issue was discovered in the tremor-script crate before 0.11.6 for Rust. A patch operation may result in a use-after-free.",
  "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" : "tremor-script"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0.7.2"
      }, {
        "fixed" : "0.11.6"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2021-45701"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/tremor-rs/tremor-runtime/pull/1217"
  }, {
    "type" : "WEB",
    "url" : "https://raw.githubusercontent.com/rustsec/advisory-db/main/crates/tremor-script/RUSTSEC-2021-0111.md"
  }, {
    "type" : "WEB",
    "url" : "https://rustsec.org/advisories/RUSTSEC-2021-0111.html"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-416" ],
    "severity" : "CRITICAL",
    "github_reviewed" : true,
    "github_reviewed_at" : "2022-01-06T13:27:33Z",
    "nvd_published_at" : "2021-12-27T00:15:00Z"
  }
}