How severe is CVE-2020-6018?

CVE-2020-6018 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-6018 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-6018?

CVE-2020-6018 affects Valvesoftware Game Networking Sockets. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-6018?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2020-6018 published?

CVE-2020-6018 was published on 2020-12-02 and last updated on 2026-06-17.

CVE-2020-6018

CVE-2020-6018 is a critical-severity vulnerability in Valvesoftware Game Networking Sockets with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 3% (86th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Valvesoftware Game Networking Sockets
Published: 2020-12-02
Last modified: 2026-06-17

Description

Valve's Game Networking Sockets prior to version v1.2.0 improperly handles long encrypted messages in function AES_GCM_DecryptContext::Decrypt() when compiled using libsodium, leading to a Stack-Based Buffer Overflow and resulting in a memory corruption and possibly even a remote code execution.

Frequently asked questions

What is CVE-2020-6018?: Valve's Game Networking Sockets prior to version v1.2.0 improperly handles long encrypted messages in function AES_GCM_DecryptContext::Decrypt() when compiled using libsodium, leading to a Stack-Based Buffer Overflow and resulting in a memory corruption and possibly even a remote code execution.
How severe is CVE-2020-6018?: CVE-2020-6018 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-6018 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-6018?: CVE-2020-6018 affects Valvesoftware Game Networking Sockets. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-6018?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2020-6018 published?: CVE-2020-6018 was published on 2020-12-02 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:valvesoftware:game_networking_sockets:*:*:*:*:*:*:*:*

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