{"document":{"category":"csaf_vex","csaf_version":"2.0","title":"CVE-2026-42909: Remote Desktop Client Remote Code Execution Vulnerability","publisher":{"category":"vendor","name":"HarborGuard Database","namespace":"https://database.harborguard.co"},"tracking":{"id":"CVE-2026-42909","status":"final","version":"1","initial_release_date":"2026-06-09T17:06:04.294Z","current_release_date":"2026-06-10T17:54:50.812Z","revision_history":[{"date":"2026-06-09T17:06:04.294Z","number":"1","summary":"Initial machine-readable export from HarborGuard."}]},"distribution":{"tlp":{"label":"WHITE"},"text":"Public CVE data; freely redistributable."},"notes":[{"category":"description","text":"Heap-based buffer overflow in Remote Desktop Client allows an unauthorized attacker to execute code over a network.","title":"CVE description"}],"references":[{"category":"self","summary":"CVE-2026-42909 on HarborGuard Database","url":"https://database.harborguard.co/cve/CVE-2026-42909"},{"category":"external","summary":"CVE Record","url":"https://www.cve.org/CVERecord?id=CVE-2026-42909"},{"category":"external","summary":"Remote Desktop Client Remote Code Execution Vulnerability","url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42909"}]},"product_tree":{"branches":[{"category":"vendor","name":"Microsoft","branches":[{"category":"product_name","name":"Remote Desktop client for Windows Desktop","branches":[{"category":"product_version_range","name":">=1.2.0.0 <1.2.7214.0","product":{"name":"Microsoft Remote Desktop client for Windows Desktop >=1.2.0.0 <1.2.7214.0","product_id":"CSAFPID-1","product_identification_helper":{"cpe":"cpe:2.3:a:microsoft:remote_desktop_client_for_windows_desktop:*:*:*:*:*:*:*:*"}}}]}]},{"category":"vendor","name":"Microsoft","branches":[{"category":"product_name","name":"Windows 10 Version 1607","branches":[{"category":"product_version_range","name":">=10.0.14393.0 <10.0.14393.9234","product":{"name":"Microsoft Windows 10 Version 1607 >=10.0.14393.0 <10.0.14393.9234","product_id":"CSAFPID-2","product_identification_helper":{"cpe":"cpe:2.3:a:microsoft:windows_10_version_1607:*:*:*:*:*:*:*:*"}}}]}]},{"category":"vendor","name":"Microsoft","branches":[{"category":"product_name","name":"Windows 10 Version 1809","branches":[{"category":"product_version_range","name":">=10.0.17763.0 <10.0.17763.8880","product":{"name":"Microsoft Windows 10 Version 1809 >=10.0.17763.0 <10.0.17763.8880","product_id":"CSAFPID-3","product_identification_helper":{"cpe":"cpe:2.3:a:microsoft:windows_10_version_1809:*:*:*:*:*:*:*:*"}}}]}]},{"category":"vendor","name":"Microsoft","branches":[{"category":"product_name","name":"Windows 10 Version 21H2","branches":[{"category":"product_version_range","name":">=10.0.19044.0 <10.0.19044.7417","product":{"name":"Microsoft Windows 10 Version 21H2 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description"}],"product_status":{"known_affected":["CSAFPID-1","CSAFPID-2","CSAFPID-3","CSAFPID-4","CSAFPID-5","CSAFPID-6","CSAFPID-7","CSAFPID-8","CSAFPID-9","CSAFPID-10","CSAFPID-11","CSAFPID-12","CSAFPID-13","CSAFPID-14","CSAFPID-15","CSAFPID-16","CSAFPID-17","CSAFPID-18","CSAFPID-19","CSAFPID-20","CSAFPID-21","CSAFPID-22"]},"scores":[{"cvss_v3":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C","baseScore":7.5,"baseSeverity":"HIGH"},"products":["CSAFPID-1","CSAFPID-2","CSAFPID-3","CSAFPID-4","CSAFPID-5","CSAFPID-6","CSAFPID-7","CSAFPID-8","CSAFPID-9","CSAFPID-10","CSAFPID-11","CSAFPID-12","CSAFPID-13","CSAFPID-14","CSAFPID-15","CSAFPID-16","CSAFPID-17","CSAFPID-18","CSAFPID-19","CSAFPID-20","CSAFPID-21","CSAFPID-22"]}],"remediations":[{"category":"vendor_fix","details":"Update to a fixed version: 1.2.7214.0, 2.0.1193.0, 6.2.9200.26132, 6.3.9600.23228, 10.0.14393.9234, 10.0.17763.8880, 10.0.19044.7417, 10.0.19045.7417, 10.0.20348.5256, 10.0.22631.7219, 10.0.26100.8655, 10.0.26100.32995, 10.0.26200.8655, 10.0.28000.2269.","product_ids":["CSAFPID-1","CSAFPID-2","CSAFPID-3","CSAFPID-4","CSAFPID-5","CSAFPID-6","CSAFPID-7","CSAFPID-8","CSAFPID-9","CSAFPID-10","CSAFPID-11","CSAFPID-12","CSAFPID-13","CSAFPID-14","CSAFPID-15","CSAFPID-16","CSAFPID-17","CSAFPID-18","CSAFPID-19","CSAFPID-20","CSAFPID-21","CSAFPID-22"],"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42909"}]}]}