What is the CVSS score of CVE-2025-27998?

CVE-2025-27998 has a CVSS 3.1 base score of 8.4 (High). CVSS vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. EPSS exploitation probability: 0.1%.

Which versions of Valvesoftware Steam Client Steam Client are affected by CVE-2025-27998?

CVE-2025-27998 presents notable security risk, a code injection vulnerability rated CVSS 8.4.

How to fix or mitigate CVE-2025-27998?

Within 30 days: Identify all affected systems and apply vendor patches as part of regular patch cycle. Validate that input sanitization is in place for all user-controlled parameters.

Valvesoftware Steam Client Steam Client CVE-2025-27998

HIGH

Code Injection (CWE-94)

2025-05-21 cve@mitre.org

RCE Code Injection

8.4

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

8.4 HIGH

AV:L/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

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

Attack Vector

Local

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

Analysis Generated

Mar 28, 2026 - 18:43 vuln.today

CVE Published

May 21, 2025 - 16:15 nvd

HIGH 8.4

DescriptionCVE.org

An issue in Valvesoftware Steam Client Steam Client 1738026274 allows attackers to escalate privileges via a crafted executable or DLL.

AnalysisAI

An issue in Valvesoftware Steam Client Steam Client 1738026274 allows attackers to escalate privileges via a crafted executable or DLL. Rated high severity (CVSS 8.4), this vulnerability is no authentication required, low attack complexity. No vendor patch available.

Technical ContextAI

This vulnerability is classified as Code Injection (CWE-94), which allows attackers to inject and execute arbitrary code within the application. An issue in Valvesoftware Steam Client Steam Client 1738026274 allows attackers to escalate privileges via a crafted executable or DLL.

Affected ProductsAI

Valvesoftware Steam Client Steam Client 1738026274.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Never evaluate user-controlled input as code. Use sandboxing, disable dangerous functions, apply strict input validation.