A denial of service vulnerability in the Range header parsing component of Rack >= 1.5.0.

Affected versions

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

• rack rack1.5.0 and later · before 2.0.9.2
• rack rack2.1.0 and later · before 2.1.4.2
• rack rack2.2.0 and later · before 2.2.6.1
• rack rack3.0.0 and later · before 3.0.4.1

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/rack/rack

  • 2.0.9.2, 2.1.4.2, 2.2.4.2, 3.0.0.1affected

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-2024-25126Rack ReDos in content type parsing (2nd degree polynomial)
  41Plan
• CVE-2024-26146Possible Denial of Service Vulnerability in Rack Header Parsing
  31Monitor
• CVE-2023-27530A DoS vulnerability exists in Rack <v3.0.4.2, <v2.2.6.3, <v2.1.4.3 and <v2.0.9.3 within in the Multipart MIME parsing code in which could al
  31Monitor
• CVE-2026-34827Rack: Algorithmic-Complexity DoS in Rack::Multipart::Parser
  30Monitor
• CVE-2026-34830Rack: Rack::Sendfile regex injection via HTTP_X_ACCEL_MAPPING header allows arbitrary file reads through nginx
  30Monitor
• CVE-2026-34829Rack: Denial of Service via Unbounded Multipart File Upload Without Content-Length
  30Monitor

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.