CVE-2021-41270

描述

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 `'` 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 `'` to prefix formulas and add the prefix to cells starting by `\t`, `\r` as well as `=`, `+`, `-` and `@`.

如何修補 CVE-2021-41270

要修補 CVE-2021-41270,請將受影響套件升級到下列已修補版本。

• —升級至 5.3.12 或更新版本
• —升級至 4.4.35 或更新版本

CVE-2021-41270 正在被利用嗎?

低 — EPSS 為 1.4%,目前沒有觀察到大規模利用活動。

受影響套件(2)

• >= 5.0.0, < 5.3.12
• >= 4.1.0, < 4.4.35

CVSS 分數

參考連結(13)

• ADVISORYnvd.nist.gov/vuln/detail/CVE-2021-41270
• PATCHgithub.com/symfony/symfony
• WEBgithub.com/FriendsOfPHP/security-advisories/blob/master/symfony/serializer/CVE-2021-41270.yaml
• WEBgithub.com/FriendsOfPHP/security-advisories/blob/master/symfony/symfony/CVE-2021-41270.yaml