CVE-2021-41267 – symfony/http-kernel

Package

Manager: composer
Name: symfony/http-kernel
Vulnerable Version: >=5.2.0 <5.3.12

Severity

Level: Medium

CVSS v3.1: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N

CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

EPSS: 0.00462 pctl0.63258

Details

Webcache Poisoning in symfony/http-kernel Description ----------- When a Symfony application is running behind a proxy or a load-balancer, you can tell Symfony to look for the `X-Forwarded-*` HTTP headers. HTTP headers that are not part of the "trusted_headers" allowed list are ignored and protect you from "Cache poisoning" attacks. In Symfony 5.2, we've added support for the `X-Forwarded-Prefix` header, but this header was accessible in sub-requests, 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` HTTP header, leading to a web cache poisoning issue. Resolution ---------- Symfony now ensures that the `X-Forwarded-Prefix` HTTP header is not forwarded to sub-requests when it is not trusted. The patch for this issue is available [here](https://github.com/symfony/symfony/commit/95dcf51682029e89450aee86267e3d553aa7c487) for branch 5.3. Credits ------- We would like to thank Soner Sayakci for reporting the issue and Jérémy Derussé for fixing the issue.

Metadata

Created: 2021-11-24T20:04:25Z
Modified: 2024-02-05T11:13:47Z
Source: https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2021/11/GHSA-q3j3-w37x-hq2q/GHSA-q3j3-w37x-hq2q.json
CWE IDs: ["CWE-444"]
Alternative ID: GHSA-q3j3-w37x-hq2q
Finding: F110
Auto approve: 1