CVE-2021-30481 | BDVDB-2026-151815 Detail

Description#

Valve Steam before 2021-04-17, when a Source engine game is installed, allows remote authenticated users to execute arbitrary code because of a buffer overflow that occurs for a Steam invite after one click.

Impact#

Per CVSS v3.1: confidentiality impact high, integrity impact high, availability impact high. Attack vector: network.

Weaknesses#

No weakness recorded in the source data.

References#

Exploit#

No public exploit known

History#

Version 12021-04-10Record published in the CVE List.
Version 22025-11-03Most recent update recorded in the CVE List.

Published

Published: 2021-04-10
Last modified: 2025-11-03

Vendor information

Vendor: Not stated
Product: Not stated

Score

8.0 High

EPSS

3.5%, Low

Estimated chance of exploitation in the next 30 days. EPSS percentile: 89.4.

KEV

Not listed in the CISA Known Exploited Vulnerabilities catalog.

Impact

Not classified

Action

No specific action is recorded in the source data. Check the references for vendor guidance.

Affected Systems

No version data in the source record.

Scoring System

CVSS v4.0

Not available

CVSS v3.1

8.0 High

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

Metric breakdown
Attack Complexity	High
Attack Vector	Network
Availability	High
Confidentiality	High
Integrity	High
Privileges Required	Low
Scope	Changed
User Interaction	Required

CVSS v3.0

Not available

CVSS v2

Not available

Source: CVE List v5 (record); CISA KEV (kev, action); FIRST EPSS (epss).