Non-Constant Time String Comparison Affecting cookie-signature Open this link in a new tab package, versions <1.0.4


0.0
medium
  • Attack Complexity

    High

  • Scope

    Changed

  • Confidentiality

    High

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  • snyk-id

    npm:cookie-signature:20160804

  • published

    29 Aug 2016

  • disclosed

    28 Jan 2014

  • credit

    tenbits

Overview

'cookie-signature' is a library for signing cookies.

Versions before 1.0.4 of the library use the built-in string comparison mechanism, ===, and not a time constant string comparison. As a result, the comparison will fail faster when the first characters in the token are incorrect. An attacker can use this difference to perform a timing attack, essentially allowing them to guess the secret one character at a time.

You can read more about timing attacks in Node.js on the Snyk blog: https://snyk.io/blog/node-js-timing-attack-ccc-ctf/

Remediation

Upgrade to 1.0.4 or greater.