Improper Neutralization of Formula Elements in a CSV File Affecting symfony package, versions <4.4.19+dfsg-3


Severity

Recommended
0.0
medium
0
10

Snyk's Security Team recommends NVD's CVSS assessment. Learn more

Threat Intelligence

EPSS
0.13% (48th percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications
  • Snyk IDSNYK-DEBIANUNSTABLE-SYMFONY-1926153
  • published25 Nov 2021
  • disclosed24 Nov 2021

Introduced: 24 Nov 2021

CVE-2021-41270  (opens in a new tab)
CWE-1236  (opens in a new tab)

How to fix?

Upgrade Debian:unstable symfony to version 4.4.19+dfsg-3 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream symfony package and not the symfony package as distributed by Debian. See How to fix? for Debian:unstable relevant fixed versions and status.

Symfony/Serializer handles serializing and deserializing data structures for Symfony, a PHP framework for web and console applications and a set of reusable PHP components. Symfony versions 4.1.0 before 4.4.35 and versions 5.0.0 before 5.3.12 are vulnerable to CSV injection, also known as formula injection. In Symfony 4.1, maintainers added the opt-in csv_escape_formulas option in the CsvEncoder, to prefix all cells starting with =, +, - or @ with a tab \t. Since then, OWASP added 2 chars in that list: Tab (0x09) and Carriage return (0x0D). This makes the previous prefix char (Tab \t) part of the vulnerable characters, and OWASP suggests using the single quote &#39; for prefixing the value. Starting with versions 4.4.34 and 5.3.12, Symfony now follows the OWASP recommendations and uses the single quote &#39; to prefix formulas and add the prefix to cells starting by \t, \r as well as =, +, - and @.

CVSS Scores

version 3.1