{"id":"CVE-2026-121953","kind":"vulnerability","aliases":["CVE-2026-121953"],"related":[],"title":"FreeRDP: malicious RDP server can crash client or run code","description":"FreeRDP before 3.32.2 has a use-after-free in the client's rdpgfx dynamic virtual channel: a duplicate-name channel with a new ChannelId overwrites the listener's single callback slot, which rdpgfx_on_close frees without clearing. A malicious RDP server can open and close such a channel, then send a PDU on the original channel to crash the client or potentially execute code.","summary":"FreeRDP's client has a use-after-free in its rdpgfx dynamic virtual channel: a duplicate-name channel overwrites a callback that is freed without being cleared. A malicious RDP server can trigger a crash of the client or potentially execute code on it.","severity":"critical","cvss":9.8,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["freerdp","package","rdp","remote-desktop"],"not_affected_if":["no-untrusted-rdp-hosts","server-only-use"],"how_to_check":"- Check the installed FreeRDP version, for example `xfreerdp --version`, and compare it with the fixed release below.\n- Find where FreeRDP is bundled in applications or packages on the machine that connect to remote desktops.","fix":"- FreeRDP: move to `3.32.2` or later.","status":"open","published_at":"2026-11-04T16:17:47+00:00","first_seen_at":"2026-11-04T16:28:11+00:00","triaged_at":"2026-11-04T16:28:38+00:00","updated_at":"2026-11-04T16:28:38+00:00","category":"package","confidence":0.6,"triage":{"at":"2026-11-04T16:28:38Z","model":"claude-haiku-5-5","output":{"fix":"- FreeRDP: move to `3.32.2` or later.","reach":"network","title":"FreeRDP: malicious RDP server can crash client or run code","impact":"high","summary":"FreeRDP's client has a use-after-free in its rdpgfx dynamic virtual channel: a duplicate-name channel overwrites a callback that is freed without being cleared. A malicious RDP server can trigger a crash of the client or potentially execute code on it.","audience":"developers","category":"package","nicknames":[],"who_cares":["freerdp","rdp","remote-desktop"],"confidence":0.6,"fix_status":"available","needs_auth":"no","worst_case":"Client crashes or attacker potentially executes code on client","analyst_note":"Confirm whether a public proof of concept exists and whether code execution is practical, using the vendor advisory and VulnCheck advisory linked in the signal.","how_to_check":"- Check the installed FreeRDP version, for example `xfreerdp --version`, and compare it with the fixed release below.\n- Find where FreeRDP is bundled in applications or packages on the machine that connect to remote desktops.","plain_action":"","needs_analyst":true,"not_affected_if":["server-only-use","no-untrusted-rdp-hosts"],"who_is_affected":"Teams whose software embeds or uses the FreeRDP client to connect to RDP servers are exposed, since the flaw is in the client and is triggered by a hostile server it connects to. Systems that only run the FreeRDP server side or never connect to untrusted RDP hosts can likely skip it, though the sources do not say this explicitly.","user_interaction":"unknown","needs_special_setup":"unknown","severity_if_unknown":"critical"},"cost_usd":0.000719,"input_tokens":4209,"output_tokens":596,"severity_before":"critical"},"analyst_status":null,"analyst_note":null,"search":"'-121953':13A,16A '-2026':12A,15A '3.32.2':69C 'callback':45B,98C 'channel':37B,42B,83C,88C,117C,125C 'channelid':92C 'clear':51B,106C 'client':7A,25B,62B,78C,129C 'close':103C,114C 'code':10A,66B,133C 'crash':6A,59B,127C 'cve':11A,14A 'desktop':22B 'duplic':40B,86C 'duplicate-nam':39B,85C 'dynam':35B,81C 'execut':65B,132C 'free':31B,75C,104C 'freed':48B 'freerdp':1A,17B,23B,67C 'listen':95C 'malici':2A,53B,108C 'name':41B,87C 'new':91C 'open':112C 'origin':124C 'overwrit':43B,93C 'packag':18B 'pdu':121C 'potenti':64B,131C 'rdp':3A,19B,54B,109C 'rdpgfx':34B,80C,101C 'remot':21B 'remote-desktop':20B 'run':9A 'send':119C 'server':4A,55B,110C 'singl':97C 'slot':99C 'trigger':57B 'use':29B,73C 'use-after-fre':28B,72C 'virtual':36B,82C 'without':49B,105C","nicknames":[],"mitigations":[],"who_affected":"Teams whose software embeds or uses the FreeRDP client to connect to RDP servers are exposed, since the flaw is in the client and is triggered by a hostile server it connects to. Systems that only run the FreeRDP server side or never connect to untrusted RDP hosts can likely skip it, though the sources do not say this explicitly.","tier":"B","verified":{},"analyst_revisit_at":null,"fix_status":"available","audience":"developers","plain_action":null,"pkeys":[],"ptokens":[],"labels":["critical","freerdp","package","rdp","remotedesktop"],"campaign_type":null,"first_public_at":"2026-10-20T17:14:38+00:00","kev":null,"cvss_vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","cvss_by":"disclosure@vulncheck.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-121953","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-121953","severity":null,"published_at":"2026-11-04T16:17:47+00:00","modified_at":"2026-11-04T16:17:47+00:00","first_seen_at":"2026-11-04T16:28:11+00:00","fetched_at":"2026-11-04T16:28:11+00:00","note":null}],"documents":[{"id":68476,"url":"https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-6wqx-rv3q-vcxp","title":"Vendor advisory: github.com","kind":"vendor","source":"nvd","publisher":"vendor","text":null,"published_at":"2026-10-20T17:14:38+00:00","relation":"advisory","confidence":null,"note":"Vendor advisory: github.com"},{"id":68477,"url":"https://www.vulncheck.com/advisories/freerdp-before-3.32.2-use-after-free-via-rdpgfx-dynamic-virtual-channel-close","title":"Third-party advisory: www.vulncheck.com","kind":"advisory","source":"nvd","publisher":"research","text":null,"published_at":null,"relation":"advisory","confidence":null,"note":"Third-party advisory: www.vulncheck.com"}],"notice":"Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai"}