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CVE-2021-30481

Published: Apr 10, 2021Updated: Nov 3, 2025 Sources: CVE List NVDCWE-120
NVD MITRE
8.0CVSSHIGH
EPSS Score
3.5%
Top 12.3%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
No Fix Available

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.

CVSS Vector Breakdown

AV:NAC:HPR:LUI:RS:CC:HI:HA:H
Exploitability
AV:NAttack Vector
Network
AC:HAttack Complexity
High
PR:LPrivileges Required
Low
UI:RUser Interaction
Required
Scope
S:CScope
Changed
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High
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Weaknesses

CWE-120

Affected Products

n/an/a
steam clientvalvesoftware
Mixed
Consumer Software / gaming
valvesoftwarecommercialUSConsumer Softwareaka steam, dota 2, game networking sockets

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

MITRE ATT&CK

2 techniques
Initial Access
Privilege Escalation
View detailed technique mapping

References

https://twitter.com/the_secret_club/status/1380868759129296900
twitter.com
https://www.youtube.com/watch?v=rNQn--9xR1Q
youtube.com
https://news.ycombinator.com/item?id=26762170
news.ycombinator.com
and 1 more references View all →

Timeline

Published
Apr 10, 2021
Last Updated
Nov 3, 2025

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