CVE-2021-30481 - Vulnerability Details - OpenCVE

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.

No CVSS v4.0

Attack Vector Network

Attack Complexity High

Privileges Required Low

Scope Changed

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction Required

No CVSS v3.0

Access Vector Network

Access Complexity Medium

Authentication Single

Confidentiality Impact Partial

Integrity Impact Partial

Availability Impact Partial

This CVE is not in the KEV list.

The EPSS score is 0.10977.

Key SSVC decision points have not yet been added.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

n/a

n/a

affected

Version	Status	Constraints
`n/a`	affected	—

Configuration 1 [-]

cpe:2.3:a:valvesoftware:steam_client:*:*:*:*:*:*:*:*

No data.

No data.

Project Subscriptions

Vendors	Products
Valvesoftware Subscribe	Steam Client Subscribe

Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

Link	Providers
https://news.ycombinator.com/item?id=26762170
https://twitter.com/floesen_/status/1337107178096881666
https://twitter.com/the_secret_club/status/1380868759129296900
https://www.youtube.com/watch?v=rNQn--9xR1Q

History

Mon, 03 Nov 2025 05:45:00 +0000

Type	Values Removed	Values Added
Description	Valve Steam through 2021-04-10, 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.	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.

Projects

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MITRE

Status: PUBLISHED

Assigner: mitre

Published: 2021-04-10T18:31:34.000Z

Updated: 2025-11-03T05:30:21.447Z

Reserved: 2021-04-10T00:00:00.000Z

Link: CVE-2021-30481

Vulnrichment

No data.

NVD

Status : Modified

Published: 2021-04-10T19:15:11.707

Modified: 2025-11-03T06:15:32.857

Link: CVE-2021-30481

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-120

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