CVE intelligence and bounded remediation

CVE-2020-26256 — Fast-csv is an npm package for parsing and formatting CSVs or any other delimited value file in node

Medium CVSS 6.5

Fast-csv is an npm package for parsing and formatting CSVs or any other delimited value file in node. In fast-cvs before version 4.3.6 there is a possible ReDoS vulnerability (Regular Expression Denial of Service) when using ignoreEmpty option when parsing. This has been patched in `v4.3.6` You will only be affected by this if you use the `ignoreEmpty` parsing option. If you do use this option it is recommended that you upgrade to the latest version `v4.3.6` This vulnerability was found using a CodeQL query which identified `EMPTY_ROW_REGEXP` regular expression as vulnerable.

Severity
Medium
CVSS
6.5 (3.1)
Published
2020-12-08
CISA KEV
Not currently listed
Ecosystem
javascript/npm
Weaknesses
CWE-400

Affected products

  • c2fo / fast-csv

Matched remediation archetype

Resource exhaustion and denial of service

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Identify attacker-influenced work factors including input size, nesting, compression, fan-out, regex cost, allocation, recursion, retries, and connection lifetime.
  • Map per-request and shared CPU, memory, disk, descriptor, thread, queue, and downstream-service limits.
  • Determine whether authentication, tenancy, quotas, and rate controls apply before expensive processing begins.

Remediate safely

  • Bound input size, nesting, expansion, work, concurrency, queue depth, retries, and execution time before resource-intensive processing.
  • Release resources on every success, error, cancellation, and timeout path and use backpressure instead of unbounded buffering.
  • Update affected components and add small deterministic tests that assert resource ceilings rather than exhausting a host.

Authoritative sources

Complete CVE record and remediation plan

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