CVE-2023-42801: Moonlight-common-c contains the core GameStream client code shared between Moonlight clients. Moonlight-common-c is vulnerable to buffer overflow star...

Description

Moonlight-common-c contains the core GameStream client code shared between Moonlight clients. Moonlight-common-c is vulnerable to buffer overflow starting in commit f57bd745b4cbed577ea654fad4701bea4d38b44c. A malicious game streaming server could exploit a buffer overflow vulnerability to crash a moonlight client. Achieving RCE is possible but unlikely, due to stack canaries in use by modern compiler toolchains. The published binaries for official clients Qt, Android, iOS/tvOS, and Embedded are built with stack canaries, but some unofficial clients may not use stack canaries. This vulnerability takes place after the pairing process, so it requires the client to be tricked into pairing to a malicious host. It is not possible to perform using a man-in-the-middle due to public key pinning that takes place during the pairing process. The bug was addressed in commit b2497a3918a6d79808d9fd0c04734786e70d5954.

Metrics

CVSS 3.1

7.6/10

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

EPSS Probability

0.79%

51.7th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-120

Affected Software

Vendor	Product	Versions
Moonlight-Stream	Moonlight-Common-C	>= 2016-10-05, < 2023-10-06
Moonlight-Stream	Moonlight	< 9.0.0
Moonlight-Stream	Moonlight	< 12.0
Moonlight-Stream	Moonlight	< 0.10.23
Moonlight-Stream	Moonlight Embedded	< 2.6.1
Moonlight-Stream	Moonlight Xbox	<= 1.14.5
Moonlight-Stream	Moonlight Tv	< 1.6.0
Moonlight-Stream	Moonlight Switch	< 0.13.4
Moonlight-Stream	Moonlight Vita	All versions
Moonlight-Stream	Moonlight Qt\/Pc	<= 5.0.0

References

Timeline

Published: Dec 14, 2023
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2023-42801?

Moonlight-common-c contains the core GameStream client code shared between Moonlight clients. Moonlight-common-c is vulnerable to buffer overflow starting in commit f57bd745b4cbed577ea654fad4701bea4d38b44c. A malicious game streaming server could exploit a buffer overflow vulnerability to crash a moonlight client. Achieving RCE is possible but unlikely, due to stack canaries in use by modern compiler toolchains. The published binaries for official clients Qt, Android, iOS/tvOS, and Embedded are built with stack canaries, but some unofficial clients may not use stack canaries. This vulnerability takes place after the pairing process, so it requires the client to be tricked into pairing to a malicious host. It is not possible to perform using a man-in-the-middle due to public key pinning that takes place during the pairing process. The bug was addressed in commit b2497a3918a6d79808d9fd0c04734786e70d5954.

How severe is CVE-2023-42801?

CVE-2023-42801 has a CVSS score of 7.6/10 (HIGH severity). The EPSS model estimates a 0.79% probability of exploitation in the next 30 days.

How do I fix CVE-2023-42801?

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.