CVE-2026-41210 (GCVE-0-2026-41210)
Vulnerability from cvelistv5 – Published: 2026-10-12 21:25 – Updated: 2026-10-13 15:02
VLAI
EPSS
VEX
Title
Moonlight Qt: Remote heap buffer overflow in Moonlight Qt H.264 SPS fixup path via crafted seq_parameter_set_id
Summary
Moonlight Qt is a GameStream client for Windows, macOS, Linux, and Steam Link. In version 6.1.0 and earlier, after a victim initiates a streaming session to a malicious host, the host can send a crafted H.264 SPS NAL when Moonlight selects a decoder path that does not advertise CAPABILITY_REFERENCE_FRAME_INVALIDATION_AVC. The SPS fixup path in app/streaming/video/ffmpeg.cpp parses the server-provided data with h264bitstream, where attacker-controlled seq_parameter_set_id is used to index the 32-entry sps_table without validation. A value of 32 or greater causes an out-of-bounds write and remote heap corruption in the Moonlight client. The demonstrated impact is a reliable client crash, while code execution is not established. This issue is fixed in version 6.2.0.
Severity
6.5 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-13 15:02 UTC
CWE
- CWE-787 - Out-of-bounds Write
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://github.com/moonlight-stream/moonlight-qt/… | x_refsource_CONFIRM |
| https://github.com/moonlight-stream/moonlight-qt/… | x_refsource_MISC |
| https://github.com/moonlight-stream/moonlight-qt/… | x_refsource_MISC |
| https://github.com/moonlight-stream/moonlight-qt/… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| moonlight-stream | moonlight-qt |
Affected:
< 6.2.0
|
guessed |
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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