Vulnerability report

Exploited in the wild High confidence Not in CISA KEV

CVE-2024-50340

symfony

Symfony / symfony · affected before 5.4.46

View live feed Monitor via API Watch CVE-2024-50340
Severity
CVSS 7.3 · High
Confidence
High
Exploit status
Exploited in the wild
EPSS
64.4%
First observed
—
Last observed
—

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2024-50340 is an unauthenticated vulnerability affecting Symfony symfony. symfony/runtime is a module for the Symphony PHP framework which enables decoupling PHP applications from global state. When the...

Is it exploited?

Yes. Previdian tracks this CVE as a known exploited vulnerability. Confidence is high. Also confirmed by third-party sources.

Who is affected?

Symfony / symfony affected before 5.4.46.

What should we do?

Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.

Overview

symfony/runtime is a module for the Symphony PHP framework which enables decoupling PHP applications from global state

symfony/runtime is a module for the Symphony PHP framework which enables decoupling PHP applications from global state. When the `register_argv_argc` php directive is set to `on` , and users call any URL with a special crafted query string, they are able to change the environment or debug mode used by the kernel when handling the request. As of versions 5.4.46, 6.4.14, and 7.1.7 the `SymfonyRuntime` now ignores the `argv` values for non-SAPI PHP runtimes.

All users are advised to upgrade. There are no known workarounds for this vulnerability.

sensiolabs Affected
symfony
Before 5.4.46 Before 6.4.14 Before 7.1.7
symfony Affected
symfony
Before 5.4.46 >= 6.0.0, < 6.4.14 >= 7.0.0, < 7.1.7
Published
06 Nov 2024
Exploitation Reported
10 Sep 2026
Attack vector
Remote
Complexity
Low
Privileges
None
User interaction
None

Tags

php nuclei_scanner

CVE References

Exploitation evidence

Why Previdian marks this CVE as exploited

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploited in the wild

The Shadowserver

Recorded 10 Sep 2026

A trusted third party reported exploitation.

Proof of concept available

GitHub

Recorded 06 Nov 2024

Public scanner or PoC coverage increases practical exploitability.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the Previdian Pro API.

Learn about Pro API access
Source Added
The Shadowserver First 2026-09-10 00:00 UTC

Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Observed signals

Request targets
User-Agents
Callback hosts
0
0
0

Request targets and User-Agents available in Pro. Callback host details available in Enterprise.

Virtual patch status

No Previdian virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.

Learn about virtual patches →

Scanner Artifacts

Scanner and exploit-framework references linked to this CVE.

Scanner Reference Detected
Nuclei https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2024/CVE-2024-50340.yaml 25 Apr 2025

Risk and context

Severity, weaknesses, and research context

CVSS v3.1

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

EPSS

64.4%

Weaknesses

Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection') CWE-74

Recent mention · Github Advisory Database (Composer)

[symfony/runtime] SymfonyRuntime CVE-2024-50340 Patch Bypass: Web Requests Can Still Set APP_ENV/APP_DEBUG via parse_str/SAPI Argv Mismatch

Description CVE-2024-50340 (GHSA-x8vp-gf4q-mw5j) addressed an issue where, with register_argc_argv=On, a crafted query string let an unauthenticated GET change the kernel environment and debug flag by feeding --env/--no-debug through $_SERVER['argv']. The fix shipped in...

Read full advisory

All Mentions

Recent mention · Github Advisory Database (Composer)

[symfony/runtime] SymfonyRuntime CVE-2024-50340 Patch Bypass: Web Requests Can Still Set APP_ENV/APP_DEBUG via parse_str/SAPI Argv Mismatch

Github Advisory Database (Composer) · 09 Jun 2026

Description CVE-2024-50340 (GHSA-x8vp-gf4q-mw5j) addressed an issue where, with register_argc_argv=On, a crafted query string let an unauthenticated GET change the kernel environment and debug flag by feeding --env/--no-debug through $_SERVER['argv']. The fix shipped in symfony/runtime 5.4.46 / 6.4.14 / 7.1.7 gated the argv read on empty($_GET) as a proxy for "is this a CLI invocation". That proxy is unsafe: parse_str() (which builds $_GET) and the web SAPI (which builds $_SERVER['argv'] from the raw query when register_argc_argv=On) do not agree on every input, so an attacker can craft a...

Recent mention · Github Advisory Database (Composer)

[symfony/symfony] SymfonyRuntime CVE-2024-50340 Patch Bypass: Web Requests Can Still Set APP_ENV/APP_DEBUG via parse_str/SAPI Argv Mismatch

Github Advisory Database (Composer) · 09 Jun 2026

Description CVE-2024-50340 (GHSA-x8vp-gf4q-mw5j) addressed an issue where, with register_argc_argv=On, a crafted query string let an unauthenticated GET change the kernel environment and debug flag by feeding --env/--no-debug through $_SERVER['argv']. The fix shipped in symfony/runtime 5.4.46 / 6.4.14 / 7.1.7 gated the argv read on empty($_GET) as a proxy for "is this a CLI invocation". That proxy is unsafe: parse_str() (which builds $_GET) and the web SAPI (which builds $_SERVER['argv'] from the raw query when register_argc_argv=On) do not agree on every input, so an attacker can craft a...

Potential Proof of Concepts

These PoCs are unverified and could contain malware. Use at your own risk.

Symfony Profiler - Remote Access via Injected Arguments

nuclei · Created Unknown

Timeline

From disclosure to observed exploitation

  1. 00:00 UTC

    Added to Previdian KEV Feed

    High-confidence, third-party attested exploitation

  2. 14:20 UTC

    Public PoC available

    Public proof-of-concept code published

  3. 00:00 UTC

    Nuclei template available

    Scanner coverage available

  4. 21:09 UTC

    CVE published

    Vulnerability disclosed publicly

  5. 17:54 UTC

    CVE ID reserved

    Identifier reserved by the CNA

Pro API

Automate this intelligence

Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

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GET /api/v2/pro/kevs/CVE-2024-50340

Free JSON includes basic KEV fields 
{
  "cve_id": "CVE-2024-50340",
  "confidence": "High",
  "cvss_score": 7.3,
  "cvss_estimated": false,
  "epss_score": 0.64429,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": false
  },
  "sensor_telemetry": { "attempts": 0, "sensors": 0 }
}