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CVE-2021-41267GHSA-Q3J3-W37X-HQ2QBIT-SYMFONY-2021-41267

Webcache Poisoning in Symfony

Published
Last modified
published
Not listed in CISA KEV
Fix
Fixed in 5.3.12
None on Exploit-DB, Metasploit or GitHub

Summary

Symfony/Http-Kernel is the HTTP kernel component for Symfony, a PHP framework for web and console applications and a set of reusable PHP components. Headers that are not part of the "trusted_headers" allowed list are ignored and protect users from "Cache poisoning" attacks. In Symfony 5.2, maintainers added support for the `X-Forwarded-Prefix` headers, but this header was accessible in SubRequest, even if it was not part of the "trusted_headers" allowed list. An attacker could leverage this opportunity to forge requests containing a `X-Forwarded-Prefix` header, leading to a web cache poisoning issue. Versions 5.3.12 and later have a patch to ensure that the `X-Forwarded-Prefix` header is not forwarded to subrequests when it is not trusted.

Timeline

  1. CVE published
  2. Record last updated

Affected versions

  • symfony symfony

    From 5.2.0 · fixed in 5.3.12

  • symfony/http-kernelPackagist

    From 5.2.0 · fixed in 5.3.12

  • symfony/symfonyPackagist

    From 5.2.0 · fixed in 5.3.12

References 4

GitHub · symfony/symfony