Vulnerability Report

CVE-2021-41267

Title: Web Cache Poisoning via X-Forwarded-Prefix in Symfony Http-Kernel

Web Cache Poisoning

Proof Of Concept

No public PoC currently indexed for CVE-2021-41267.

CWE Category CWE-444
Published Date Nov 24, 2021
Modified Date Nov 21, 2024
Exploit Status Not Found
Score 6.5 CVSS v3.1
Exploit Probability (EPSS)
1.24%

Vulnerability Summary

CVE-2021-41267: 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.

Impacted Vendors

S
sensiolabs 1
A
auth0 1

Reference Links

https://github.com/symfony/symfony/commit/95dcf51682029e89450aee86267e3d553aa7c487 https://github.com/symfony/symfony/pull/44243 https://github.com/symfony/symfony/releases/tag/v5.3.12 https://github.com/symfony/symfony/security/advisories/GHSA-q3j3-w37x-hq2q https://github.com/symfony/symfony/commit/95dcf51682029e89450aee86267e3d553aa7c487 https://github.com/symfony/symfony/pull/44243 https://github.com/symfony/symfony/releases/tag/v5.3.12 https://github.com/symfony/symfony/security/advisories/GHSA-q3j3-w37x-hq2q
CVSS v3.1
Source Entity [email protected]
Severity MEDIUM
6.5
Attack Vector
NETWORK
Complexity
LOW
Privileges
N/A
Interaction
REQUIRED
Confidentiality
N/A
Integrity
N/A
Availability
N/A
Scope
UNCHANGED
RAW VECTOR CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
CVSS v2.0
Source Entity [email protected]
Severity MEDIUM
4.3
Access Vector
N/A
Authentication
N/A
RAW VECTOR AV:N/AC:M/Au:N/C:N/I:P/A:N

Associated Attack Patterns (CAPEC)

Total: Patterns

CVE-2021-41267 Exploits & PoCs (Proof Of Concept)

No public PoCs found in our database for this CVE.

MODIFIED

Vulnerability data or affected products updated.

PUBLISHED

Vulnerability first announced in NVD.

Attack Vector Matrix

Access Vector NETWORK
Complexity LOW
Privileges N/A
Interaction REQUIRED
CVSS Vector String CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N

Affected Stack

No specific products linked.