CVE-2021-22902: The actionpack ruby gem (a framework for handling and responding to web requests in Rails) before 6.0.3.7, 6.1.3.2 suffers from a possible d

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

• rubyonrails rails6.0.0 and later · before 6.0.3.7
• rubyonrails rails6.1.0 and later · before 6.1.0.2

Versions reported by the vendor

Affected version ranges reported by the assigning authority (hackerone). Independent of NVD's CPE analysis and usually ahead of it.

• n/a https://github.com/rails/rails

  • Fixed in 6.0.3.7, 6.1.3.2affected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

Other highest-scoring records for the same primary product.

• CVE-2019-5418There is a File Content Disclosure vulnerability in Action View <5.2.2.1, <5.1.6.2, <5.0.7.2, <4.2.11.1 and v3 where specially crafted accepKEV
  90Now
• CVE-2016-0752Directory traversal vulnerability in Action View in Ruby on Rails before 3.2.22.1, 4.0.x and 4.1.x before 4.1.14.1, 4.2.x before 4.2.5.1, anKEV
  89Now
• CVE-2019-5420A remote code execution vulnerability in development mode Rails <5.2.2.1, <6.0.0.beta3 can allow an attacker to guess the automatically gene
  66This week

Published before and after this one in the same product

• ← EarlierCVE-2021-22881Feb 11, 2021 · The Host Authorization middleware in Action Pack before 6.1.2.1, 6.0.3.5 suffers from an open redirect vulnerability.
  50Plan
• ← EarlierCVE-2021-22885May 27, 2021 · A possible information disclosure / unintended method execution vulnerability in Action Pack >= 2.0.0 when using the `redirect_to` or `polym
  31Monitor
• Later →CVE-2021-22903Jun 11, 2021 · The actionpack ruby gem before 6.1.3.2 suffers from a possible open redirect vulnerability.
  24Monitor

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Root cause

Code that parses nested structures sets no depth or size limit. A small input can turn into a disproportionate processing load.

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

1function expand(node) {2  return node.children.map(expand);3}

1const MAX_DEPTH = 32;2function expand(node, depth = 0) {3  if (depth > MAX_DEPTH) throw new Error("too deep");4  return node.children.map((c) => expand(c, depth + 1));5}

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.