{"id":"CVE-2026-41210","title":"Moonlight Qt is a GameStream client for Windows, macOS, Linux, and Steam Link","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 selec…","severity":"medium","cvss":6.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","cwe":["CWE-787"],"published":"2026-10-12","updated":"2026-10-12","sourceUpdated":"2026-10-12T22:17:03.997","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-41210","references":[{"url":"https://github.com/moonlight-stream/moonlight-qt/commit/3e24a7a1a5369163482ce5a76d5232536e03c53f","label":"security-advisories@github.com"},{"url":"https://github.com/moonlight-stream/moonlight-qt/commit/b7adc70ea474f7448c6185081ad9fc87b0b47cf0","label":"security-advisories@github.com"},{"url":"https://github.com/moonlight-stream/moonlight-qt/releases/tag/v6.2.0","label":"security-advisories@github.com"},{"url":"https://github.com/moonlight-stream/moonlight-qt/security/advisories/GHSA-5rvh-v25g-vrgv","label":"security-advisories@github.com"}],"tags":["nvd"],"ingestedAt":"2026-10-12T23:07:25.635Z","slug":"CVE-2026-41210","body":"## Overview\n\nMoonlight 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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":36,"depthScoreParts":{"impact":35.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}