CVE-2026-47767: Symfony: SymfonyRuntime CVE-2024-50340 Patch Bypass: Web Requests Can Still Set APP_ENV/APP_DEBUG via parse_str/SAPI Argv Mismatch

Description

Symfony is a PHP framework for web and console applications and a set of reusable PHP components. From 5.4.46 until 5.4.52, 6.4.40, 7.4.12, and 8.0.12, the CVE-2024-50340 fix gated runtime argv parsing on empty($_GET), but parse_str() and the web SAPI can disagree, allowing a crafted query string to leave $_GET empty while $_SERVER['argv'] still carries attacker-controlled --env or --no-debug flags that change APP_ENV or APP_DEBUG. This issue is fixed in versions 5.4.52, 6.4.40, 7.4.12, and 8.0.12.

CVSS vector

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

Attack vector

Network

Complexity

Low

Privileges

None

User interaction

None

Confidentiality

High

Integrity

High

Availability

High

Scope

Unchanged

Exploitation

Is it being used?

Exploit prediction (EPSS)0.7% · higher than 54% of CVEs

Exploited in the wildNo evidence yet

CISA KEVNot listed

Ransomware campaign useNot known

Affected products

Which versions

RU

runtime · symfony

>= 5.4.46, < 5.4.52; >= 6.4.14, < 6.4.40; >= 7.1.7, < 7.4.12; >= 8.0.0-BETA1, < 8.0.12 · source: vendor

SY

symfony · symfony

>= 5.4.46, < 5.4.52; >= 6.4.14, < 6.4.40; >= 7.1.7, < 7.4.12; >= 8.0.0-BETA1, < 8.0.12 · source: vendor, NVD