CVE-2020-6017

Name: CVE-2020-6017
Creator: NVD / NIST
Published: 2020-12-03T14:15:11.02+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 3.10%

Last modified Jun 17, 2026

CVE-2020-6017 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. Valve's Game Networking Sockets prior to version v1.2.0 improperly handles long unreliable segments in function SNP_ReceiveUnreliableSegment() when configured to support plain-text messages, leading to a Heap-Based Buffer Overflow and resulting in a memory corruption and possibly even a remote code execution.. EPSS estimates a 3.10% chance of exploitation in the next 30 days.

Description

Valve's Game Networking Sockets prior to version v1.2.0 improperly handles long unreliable segments in function SNP_ReceiveUnreliableSegment() when configured to support plain-text messages, leading to a Heap-Based Buffer Overflow and resulting in a memory corruption and possibly even a remote code execution.

Metrics

CVSS 3.1

9.8/10

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

EPSS Probability

3.10%

86.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Valvesoftware	Game Networking Sockets	< 1.2.0

References

https://github.com/ValveSoftware/GameNetworkingSockets/commit/e0c86dcb9139771db3db0cfdb1fb8bef0af19c43Patch, Third Party Advisory
https://research.checkpoint.com/2020/game-on-finding-vulnerabilities-in-valves-steam-sockets/Exploit, Third Party Advisory
https://github.com/ValveSoftware/GameNetworkingSockets/commit/e0c86dcb9139771db3db0cfdb1fb8bef0af19c43Patch, Third Party Advisory
https://research.checkpoint.com/2020/game-on-finding-vulnerabilities-in-valves-steam-sockets/Exploit, Third Party Advisory

Timeline

Published: Dec 3, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-6017?

How severe is CVE-2020-6017?

CVE-2020-6017 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 3.10% probability of exploitation in the next 30 days.

How do I fix CVE-2020-6017?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-6017?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST