CVE-2018-1000539: Json jwt Json-jwt Did Not Verify The Vulnerability

MODERATE
Advisory Identifier: GHSA-mj4x-wcxf-hm8x
Share
CVSS 5.3
CWE-347
Published
Advisory Summary

CVE-2018-1000539 is a MODERATE (CVSS 5.3) json-jwt did not verify the vulnerability (CWE-347: Improper Verification of Cryptographic Signature) affecting Json jwt libraries in the RubyGems ecosystem. The issue involves json-jwt did not verify the cryptographic signature for data. Remediation is available by upgrading affected packages to version 1.9.4.

CVE-2018-1000539 at a Glance

CVE Identifier CVE-2018-1000539
GHSA Identifier GHSA-mj4x-wcxf-hm8x
Severity MODERATE
CVSS v3.1 Base Score 5.3
CWE Classification CWE-347: Improper Verification of Cryptographic Signature
Affected Product Json jwt
Package Ecosystem RubyGems
Published Date
Last Updated

Security Impact

CVSS: 5.3

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:L/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 None (C:N)
Integrity Low (I:L)
Availability None (A:N)

How to Fix CVE-2018-1000539

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

json-jwt fixed: 1.9.4 
Upgrade json-jwt to 1.9.4
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 json-jwt

How to Check if You Are Affected

To determine whether your application is affected by CVE-2018-1000539, inspect your project dependencies for Json jwt:

inspect dependencies for json-jwt

Analyze the terminal output to locate any version of Json jwt in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.9.4), 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-347: Improper Verification of Cryptographic Signature, where the product does not verify, or incorrectly verifies, the cryptographic signature for data. In Json jwt, 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

The json-jwt rubygem version >= 0.5.0 && < 1.9.4 contains a CWE-347: Improper Verification of Cryptographic Signature vulnerability in Decryption of AES-GCM encrypted JSON Web Tokens that can result in Attacker can forge a authentication tag. This attack appear to be exploitable via network connectivity. This vulnerability appears to have been fixed in 1.9.4 and later.

CVE-2018-1000539 Affected Json jwt Versions

1 component(s)
Fixed Versions:
1.9.4
Product / Package Ecosystem Affected Versions Fixed Version
json-jwt
gem/json-jwt
RubyGems
≥ 0.5.1
< 1.9.4
1.9.4

References

NVD — CVE-2018-1000539 NVD
https://nvd.nist.gov/vuln/detail/CVE-2018-1000539
Json jwt Source Repository REPOSITORY
https://github.com/nov/json-jwt/pull/62
Security Fix Commit FIX COMMIT
https://github.com/nov/json-jwt/commit/a3b2147f0f6d9aca653e7a30e453d3a92b33413f
Json jwt Source Repository REPOSITORY
https://github.com/nov/json-jwt
Json jwt Source Repository REPOSITORY
https://github.com/rubysec/ruby-advisory-db/blob/master/gems/json-jwt/CVE-2018-1000539.yml
Json jwt Security Information SECURITY
https://www.debian.org/security/2018/dsa-4283

Frequently Asked Questions

What is CVE-2018-1000539?
CVE-2018-1000539 is a security vulnerability in Json jwt involving Json-jwt did not verify the cryptographic signature for data under CWE-347: Improper Verification of Cryptographic Signature.
Which Json jwt versions are affected?
Affected versions include releases prior to 1.9.4 across affected packages: json-jwt.
What version fixes CVE-2018-1000539?
Upgrading to 1.9.4 (or the latest patched release for your respective branch) resolves the vulnerability.
Is json-jwt affected?
Yes, json-jwt is affected in releases prior to 1.9.4. Upgrade your dependency to 1.9.4 or later.
What is the CVSS score of CVE-2018-1000539?
CVE-2018-1000539 has a CVSS v3.1 base score of 5.3 (MODERATE) with vector string CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.
What CWE is associated with CVE-2018-1000539?
CVE-2018-1000539 is classified under CWE-347: Improper Verification of Cryptographic Signature (The product does not verify, or incorrectly verifies, the cryptographic signature for data.).
How can I check RubyGems dependencies for CVE-2018-1000539?
Run the dependency tree command: 'inspect dependencies for json-jwt'. 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-mj4x-wcxf-hm8x",
  "modified" : "2023-08-25T23:55:12Z",
  "published" : "2018-07-31T18:13:51Z",
  "aliases" : [ "CVE-2018-1000539" ],
  "summary" : "Json-jwt did not verify the cryptographic signature for data",
  "details" : "The json-jwt rubygem version >= 0.5.0 && < 1.9.4 contains a CWE-347: Improper Verification of Cryptographic Signature vulnerability in Decryption of AES-GCM encrypted JSON Web Tokens that can result in Attacker can forge a authentication tag. This attack appear to be exploitable via network connectivity. This vulnerability appears to have been fixed in 1.9.4 and later.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "RubyGems",
      "name" : "json-jwt"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0.5.1"
      }, {
        "fixed" : "1.9.4"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2018-1000539"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/nov/json-jwt/pull/62"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/nov/json-jwt/commit/a3b2147f0f6d9aca653e7a30e453d3a92b33413f"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/nov/json-jwt"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/rubysec/ruby-advisory-db/blob/master/gems/json-jwt/CVE-2018-1000539.yml"
  }, {
    "type" : "WEB",
    "url" : "https://www.debian.org/security/2018/dsa-4283"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-347" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2020-06-16T21:46:30Z",
    "nvd_published_at" : null
  }
}