{"id":"CVE-2021-30481","aliases":["EUVD-2021-17404","GHSA-3jx7-82j9-5prx"],"status":"published","title":"Valve Steam through 2021-04-10, when a Source engine game is installed, allows remote...","description":"Valve Steam before 2021-04-17, when a Source engine game is installed, allows remote authenticated users to execute arbitrary code because of a buffer overflow that occurs for a Steam invite after one click.","severity":{"version":"3.1","score":8,"vector":"CVSS:3.1/AC:H/AV:N/A:H/C:H/I:H/PR:L/S:C/UI:R","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.03533,"percentile":0.89346,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":true,"fix_available":false},"cwes":["CWE-120"],"published":"2021-04-10T18:31:34Z","modified":"2026-06-17T03:50:19Z","exploits":[{"source":"pocgithub","id":"floesen/CVE-2021-30481","title":"floesen/CVE-2021-30481","date":"2021-04-17","url":"https://github.com/floesen/CVE-2021-30481"}],"products":[{"vendor":"valvesoftware","product":"steam_client"}],"references":[{"url":"https://twitter.com/the_secret_club/status/1380868759129296900","tags":["x_refsource_MISC","x_transferred","Exploit","Third Party Advisory"]},{"url":"https://www.youtube.com/watch?v=rNQn--9xR1Q","tags":["x_refsource_MISC","x_transferred","Exploit","Third Party Advisory"]},{"url":"https://news.ycombinator.com/item?id=26762170","tags":["x_refsource_MISC","x_transferred","Issue Tracking","Third Party Advisory"]},{"url":"https://twitter.com/floesen_/status/1337107178096881666","tags":["x_refsource_MISC","x_transferred","Third Party Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-30481"},{"url":"https://github.com/advisories/GHSA-3jx7-82j9-5prx"}],"sources":{"cve":[{"id":"CVE-2021-30481","description":"Valve Steam before 2021-04-17, when a Source engine game is installed, allows remote authenticated users to execute arbitrary code because of a buffer overflow that occurs for a Steam invite after one click.","status":"published","published":"2021-04-10T18:31:34Z","modified":"2025-11-03T05:30:21.447Z","cvss":[{"version":"3.1","score":8,"vector":"CVSS:3.1/AC:H/AV:N/A:H/C:H/I:H/PR:L/S:C/UI:R","level":"high","assessor":"cna"}],"updated_at":"2026-11-02T14:33:01.852999Z"}],"euvd":[{"id":"EUVD-2021-17404","description":"Valve Steam before 2021-04-17, when a Source engine game is installed, allows remote authenticated users to execute arbitrary code because of a buffer overflow that occurs for a Steam invite after one click.","status":"published","published":"2021-04-10T18:31:34Z","modified":"2025-11-03T05:30:21Z","cvss":[{"version":"3.1","score":8,"vector":"CVSS:3.1/AC:H/AV:N/A:H/C:H/I:H/PR:L/S:C/UI:R","level":"high"}],"updated_at":"2026-11-02T19:49:35.368666Z"}],"ghsa":[{"id":"GHSA-3jx7-82j9-5prx","title":"Valve Steam through 2021-04-10, when a Source engine game is installed, allows remote...","description":"Valve Steam through 2021-04-10, when a Source engine game is installed, allows remote authenticated users to execute arbitrary code because of a buffer overflow that occurs for a Steam invite after one click.","status":"published","published":"2022-05-24T17:47:04Z","modified":"2024-04-04T03:06:04Z","cvss":[{"version":"3.1","score":9,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H","level":"critical"}],"cwes":["CWE-120"],"updated_at":"2026-11-02T14:56:13.784244Z"}],"nvd":[{"id":"CVE-2021-30481","description":"Valve Steam before 2021-04-17, when a Source engine game is installed, allows remote authenticated users to execute arbitrary code because of a buffer overflow that occurs for a Steam invite after one click.","status":"published","published":"2021-04-10T19:15:11.707Z","modified":"2026-06-17T03:50:19.35Z","cvss":[{"version":"3.1","score":8,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:H","level":"high","assessor":"secondary"},{"version":"3.1","score":9,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H","level":"critical","assessor":"primary"},{"version":"2.0","score":6,"vector":"AV:N/AC:M/Au:S/C:P/I:P/A:P","level":"medium","assessor":"primary"}],"cwes":["CWE-120"],"updated_at":"2026-11-02T14:06:51.610648Z"}]}}