What is the CVSS score of CVE-2021-24030?

CVE-2021-24030 has a CVSS 3.1 base score of 9.8 (Critical). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. EPSS exploitation probability: 1.7%.

Facebook CVE-2021-24030

CRITICAL

Improper Neutralization of Argument Delimiters in a Command ('Argument Injection') (CWE-88)

2021-03-10 cve-assign@fb.com

RCE Facebook Gameroom

9.8

CVSS 3.1 · NVD

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Vulnerability Assessment

Weakness	CWE CWE-88 OWASP Top 10:2025 A05:2025 - Injection ASVS 5.0 V1 - Encoding and Sanitization Argument sanitization
Impact	CVSS score of 9.8 (CRITICAL). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required.
Exploit ScenarioDerived	This vulnerability can be exploited remotely over the network. Successful exploitation could compromise the critical-severity affected system.

Act Now Prioritize within 24-48h. Why: CRITICAL severity.

No patch listed yet 1.7% exploitation probability (EPSS)

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AnalysisAI

The fbgames protocol handler registered as part of Facebook Gameroom does not properly quote arguments passed to the executable. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.

Affects your stack

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Technical ContextAI · show details

This vulnerability is classified under CWE-88. The fbgames protocol handler registered as part of Facebook Gameroom does not properly quote arguments passed to the executable. That allows a malicious URL to cause code execution.26.0. Affected products include: Facebook Gameroom.

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Exploit and PoC references, threat intelligence from 22 sources

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Severity by source

NVD PRIMARY 9.8 CRITICAL

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

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

DescriptionNVD

The fbgames protocol handler registered as part of Facebook Gameroom does not properly quote arguments passed to the executable. That allows a malicious URL to cause code execution. This issue affects versions prior to v1.26.0.

Threat Intelligence Overview

EPSS Score

1.7%

Top 26% exploitable

Data Quality

2 sources

Confidence: Low

NVD

CVE.org

EPSS

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue

Severity CRITICAL

CISA KEV No

Public POC No

EPSS 1.7%

Patch available No

Active threat No

Deciding rule

CRITICAL severity

What every action level means

Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.

Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.

This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.

This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.

Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision· derived

Scheduled

Exploitation· derived

None

System Exposure· derived

Open

Automatable· derived

Yes

Human Impact· derived

Medium

Priority Score

Low Medium High Critical

KEV: 0

EPSS: +2

CVSS: +49

PoC: 0

Weaponized: 0

Threat intel: 0

Gov advisory: 0

Attack Technique

Remote Code Execution CRITICAL

Remote Code Execution represents the critical moment when an attacker successfully runs arbitrary code on a target system without physical access.

Affected Products (CPE)NVD

cpe:2.3:a:facebook:gameroom:*:*:*:*:*:*:*:*

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Same weakness CWE-88 – Improper Neutralization of Argument Delimiters in a Command ('Argument Injection')

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CVE-2025-57791 MEDIUM POC

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CVE-2018-17456 CRITICAL POC

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CVE-2018-19518 HIGH POC

7.5

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CVE-2020-5792 HIGH POC

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CVE-2015-3113 CRITICAL POC

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References

Advisories & patches

ADVISORY https://www.facebook.com/security/advisories/cve-2021-24030

Search Externally

GitHub PoC

Exploit-DB PacketStorm Snyk Rapid7 Nuclei Templates Trickest PoC

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