CVE-2019-16882: String interner Use After Free Vulnerability

HIGH
Advisory Identifier: GHSA-49fq-pw77-6qxj
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CVSS 7.5
CWE-416
Published
Advisory Summary

CVE-2019-16882 is a HIGH (CVSS 7.5) use after free vulnerability (CWE-416: Use After Free) affecting String interner libraries in the crates.io ecosystem. The issue involves use after free in string-interner. Remediation is available by upgrading affected packages to version 0.7.1, 0.6.4.

CVE-2019-16882 at a Glance

CVE Identifier CVE-2019-16882
GHSA Identifier GHSA-49fq-pw77-6qxj
Severity HIGH
CVSS v3.1 Base Score 7.5
CWE Classification CWE-416: Use After Free
Affected Product String interner
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:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N).

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 None (I:N)
Availability None (A:N)

How to Fix CVE-2019-16882

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

string-interner fixed: 0.7.1 
Upgrade string-interner to 0.7.1
string-interner fixed: 0.6.4 
Upgrade string-interner to 0.6.4
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 string-interner

How to Check if You Are Affected

To determine whether your application is affected by CVE-2019-16882, inspect your project dependencies for String interner:

inspect dependencies for string-interner

Analyze the terminal output to locate any version of String interner in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.7.1), 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-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 String interner, 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 this crate did not clone contained strings when an interner is cloned. Interners have raw pointers to the contained strings, and they keep pointing the strings which the old interner owns, after the interner is cloned. If a new cloned interner is alive and the old original interner is dead, the new interner has dangling pointers to the old interner's storage, which is already dropped. This allows an attacker to read the already freed memory. The dangling pointers are used by the interners to check a string is already interned. An attacker can do brute force attack to get the data pointed by the dangling pointer.

CVE-2019-16882 Affected String interner Versions

2 component(s)
Fixed Versions:
0.7.10.6.4
Product / Package Ecosystem Affected Versions Fixed Version
string-interner
 crates.io
≥ 0.7.0
< 0.7.1
0.7.1
string-interner
 crates.io
< 0.6.4
0.6.4

References

NVD — CVE-2019-16882 NVD
https://nvd.nist.gov/vuln/detail/CVE-2019-16882
String interner Source Repository REPOSITORY
https://github.com/Robbepop/string-interner/issues/9
String interner Source Repository REPOSITORY
https://github.com/Robbepop/string-interner/pull/10
Security Fix Commit FIX COMMIT
https://github.com/Robbepop/string-interner/commit/d91dac0cfe42512526879cdfaac0b81beff54089
String interner Source Repository REPOSITORY
https://github.com/Robbepop/string-interner
rustsec.org/advisories/rustsec-... WEB
https://rustsec.org/advisories/RUSTSEC-2019-0023.html

Frequently Asked Questions

What is CVE-2019-16882?
CVE-2019-16882 is a security vulnerability in String interner involving Use after free in string-interner under CWE-416: Use After Free.
Which String interner versions are affected?
Affected versions include releases prior to 0.7.1, 0.6.4 across affected packages: string-interner.
What version fixes CVE-2019-16882?
Upgrading to 0.7.1, 0.6.4 (or the latest patched release for your respective branch) resolves the vulnerability.
Is string-interner affected?
Yes, string-interner is affected in releases prior to 0.7.1, 0.6.4. Upgrade your dependency to 0.7.1, 0.6.4 or later.
What is the CVSS score of CVE-2019-16882?
CVE-2019-16882 has a CVSS v3.1 base score of 7.5 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.
What CWE is associated with CVE-2019-16882?
CVE-2019-16882 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-2019-16882?
Run the dependency tree command: 'inspect dependencies for string-interner'. 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-49fq-pw77-6qxj",
  "modified" : "2023-06-13T21:55:41Z",
  "published" : "2021-08-25T20:44:15Z",
  "aliases" : [ "CVE-2019-16882" ],
  "summary" : "Use after free in string-interner",
  "details" : "Affected versions of this crate did not clone contained strings when an interner is cloned. Interners have raw pointers to the contained strings, and they keep pointing the strings which the old interner owns, after the interner is cloned. If a new cloned interner is alive and the old original interner is dead, the new interner has dangling pointers to the old interner's storage, which is already dropped.\n\nThis allows an attacker to read the already freed memory. The dangling pointers are used by the interners to check a string is already interned. An attacker can do brute force attack to get the data pointed by the dangling pointer.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "crates.io",
      "name" : "string-interner"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0.7.0"
      }, {
        "fixed" : "0.7.1"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "crates.io",
      "name" : "string-interner"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "0.6.4"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2019-16882"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/Robbepop/string-interner/issues/9"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/Robbepop/string-interner/pull/10"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/Robbepop/string-interner/commit/d91dac0cfe42512526879cdfaac0b81beff54089"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/Robbepop/string-interner"
  }, {
    "type" : "WEB",
    "url" : "https://rustsec.org/advisories/RUSTSEC-2019-0023.html"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-416" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2021-08-19T21:23:01Z",
    "nvd_published_at" : null
  }
}