CVE-2021-43172: Routinator Routinator Infinite Loop Vulnerability Vulnerability

HIGH
Advisory Identifier: GHSA-m3x9-623g-35c4
Share
CVSS 7.5
CWE-835 CWE-674
Published
Advisory Summary

CVE-2021-43172 is a HIGH (CVSS 7.5) routinator infinite loop vulnerability vulnerability (CWE-835: Loop with Unreachable Exit Condition ('Infinite Loop')) affecting Routinator libraries in the crates.io ecosystem. The issue involves routinator infinite loop vulnerability. Remediation is available by upgrading affected packages to version 0.10.2.

CVE-2021-43172 at a Glance

CVE Identifier CVE-2021-43172
GHSA Identifier GHSA-m3x9-623g-35c4
Severity HIGH
CVSS v3.1 Base Score 7.5
CWE Classification CWE-835: Loop with Unreachable Exit Condition ('Infinite Loop')
Affected Product Routinator
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:N/I:N/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 None (C:N)
Integrity None (I:N)
Availability High (A:H)

How to Fix CVE-2021-43172

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

routinator fixed: 0.10.2 
Upgrade routinator to 0.10.2
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 routinator

How to Check if You Are Affected

To determine whether your application is affected by CVE-2021-43172, inspect your project dependencies for Routinator:

inspect dependencies for routinator

Analyze the terminal output to locate any version of Routinator in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.10.2), 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-835: Loop with Unreachable Exit Condition ('Infinite Loop'), where the product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop. In Routinator, 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

NLnet Labs Routinator prior to 0.10.2 happily processes a chain of RRDP repositories of infinite length causing it to never finish a validation run. In RPKI, a CA can choose the RRDP repository it wishes to publish its data in. By continuously generating a new child CA that only consists of another CA using a different RRDP repository, a malicious CA can create a chain of CAs of de-facto infinite length. Routinator prior to version 0.10.2 did not contain a limit on the length of such a chain and will therefore continue to process this chain forever. As a result, the validation run will never finish, leading to Routinator continuing to serve the old data set or, if in the initial validation run directly after starting, never serve any data at all.

CVE-2021-43172 Affected Routinator Versions

1 component(s)
Fixed Versions:
0.10.2
Product / Package Ecosystem Affected Versions Fixed Version
routinator
 crates.io
< 0.10.2
0.10.2

References

NVD — CVE-2021-43172 NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-43172
Routinator Source Repository REPOSITORY
https://github.com/NLnetLabs/routinator/pull/665/commits/2f1c47378e3439cb89e084cdad6b759bbc8a72b8
www.nlnetlabs.nl/downloads/routinato... WEB
https://www.nlnetlabs.nl/downloads/routinator/CVE-2021-43172_CVE-2021-43173_CVE-2021-43174.txt

Frequently Asked Questions

What is CVE-2021-43172?
CVE-2021-43172 is a security vulnerability in Routinator involving Routinator infinite loop vulnerability under CWE-835: Loop with Unreachable Exit Condition ('Infinite Loop').
Which Routinator versions are affected?
Affected versions include releases prior to 0.10.2 across affected packages: routinator.
What version fixes CVE-2021-43172?
Upgrading to 0.10.2 (or the latest patched release for your respective branch) resolves the vulnerability.
Is routinator affected?
Yes, routinator is affected in releases prior to 0.10.2. Upgrade your dependency to 0.10.2 or later.
What is the CVSS score of CVE-2021-43172?
CVE-2021-43172 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:N/I:N/A:H.
What CWE is associated with CVE-2021-43172?
CVE-2021-43172 is classified under CWE-835: Loop with Unreachable Exit Condition ('Infinite Loop') (The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop.).
How can I check crates.io dependencies for CVE-2021-43172?
Run the dependency tree command: 'inspect dependencies for routinator'. 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-m3x9-623g-35c4",
  "modified" : "2023-07-13T17:03:13Z",
  "published" : "2022-05-24T19:20:05Z",
  "aliases" : [ "CVE-2021-43172" ],
  "summary" : "Routinator infinite loop vulnerability",
  "details" : "NLnet Labs Routinator prior to 0.10.2 happily processes a chain of RRDP repositories of infinite length causing it to never finish a validation run. In RPKI, a CA can choose the RRDP repository it wishes to publish its data in. By continuously generating a new child CA that only consists of another CA using a different RRDP repository, a malicious CA can create a chain of CAs of de-facto infinite length. Routinator prior to version 0.10.2 did not contain a limit on the length of such a chain and will therefore continue to process this chain forever. As a result, the validation run will never finish, leading to Routinator continuing to serve the old data set or, if in the initial validation run directly after starting, never serve any data at all.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "crates.io",
      "name" : "routinator"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "0.10.2"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2021-43172"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/NLnetLabs/routinator/pull/665/commits/2f1c47378e3439cb89e084cdad6b759bbc8a72b8"
  }, {
    "type" : "WEB",
    "url" : "https://www.nlnetlabs.nl/downloads/routinator/CVE-2021-43172_CVE-2021-43173_CVE-2021-43174.txt"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-674", "CWE-835" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2023-07-13T17:03:13Z",
    "nvd_published_at" : "2021-11-09T17:15:00Z"
  }
}