{"id":"CVE-2026-93524","kind":"vulnerability","aliases":["CVE-2026-93524"],"related":[],"title":"X.Org X Server: keyboard map check lets clients read server memory","description":"A buffer overread in CheckKeySyms() in X.Org X Server before 21.1.25 and XWayland before 24.1.14 could be used by authenticated X clients to leak small amounts of information from X server memory or potentially crash the X server.","summary":"A buffer overread in CheckKeySyms() in X.Org X Server before 21.1.25 and XWayland before 24.1.14 lets an authenticated X client read small amounts of server memory. It can also crash the X server.","severity":"medium","cvss":6.9,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["desktop","infrastructure","linux","x11","xwayland"],"not_affected_if":["no-untrusted-x-clients","wayland-only"],"how_to_check":"- Run `Xorg -version` or `X -version` to see the X.Org Server version.\n- Run `Xwayland -version` to check the XWayland version.","fix":"- Upgrade X.Org X Server to `21.1.25` or later.\n- Upgrade XWayland to `24.1.14` or later.","status":"open","published_at":"2026-10-28T17:18:53+00:00","first_seen_at":"2026-10-28T17:34:10+00:00","triaged_at":"2026-10-28T17:36:24+00:00","updated_at":"2026-10-28T17:36:24+00:00","category":"infrastructure","confidence":0.6,"triage":{"at":"2026-10-28T17:36:24Z","model":"claude-haiku-5-5","output":{"fix":"- Upgrade X.Org X Server to `21.1.25` or later.\n- Upgrade XWayland to `24.1.14` or later.","reach":"local","title":"X.Org X Server: keyboard map check lets clients read server memory","impact":"low","summary":"A buffer overread in CheckKeySyms() in X.Org X Server before 21.1.25 and XWayland before 24.1.14 lets an authenticated X client read small amounts of server memory. It can also crash the X server.","category":"infrastructure","nicknames":[],"who_cares":["linux","x11","xwayland","desktop"],"confidence":0.6,"needs_auth":"yes","worst_case":"Small memory leak or X server crash by an authenticated client.","analyst_note":"","how_to_check":"- Run `Xorg -version` or `X -version` to see the X.Org Server version.\n- Run `Xwayland -version` to check the XWayland version.","needs_analyst":false,"not_affected_if":["wayland-only","no-untrusted-x-clients"],"who_is_affected":"Systems running X.Org X Server before 21.1.25 or XWayland before 24.1.14. The attacker must already be an authenticated X client on the display, so machines with no untrusted local X clients carry less risk. Wayland-only systems without XWayland are not affected by the XWayland part.","user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"medium"},"cost_usd":0.000581,"input_tokens":3310,"output_tokens":500,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-2026':13A,16A '-93524':14A,17A '21.1.25':33B,66C '24.1.14':37B,70C 'also':51B 'amount':45B,81C 'authent':40B,75C 'buffer':24B,57C 'check':6A 'checkkeysym':27B,60C 'client':8A,42B,77C 'could':71C 'crash':52B,90C 'cve':12A,15A 'desktop':18B 'inform':83C 'infrastructur':19B 'keyboard':4A 'leak':79C 'let':7A,38B 'linux':20B 'map':5A 'memori':11A,48B,87C 'overread':25B,58C 'potenti':89C 'read':9A,43B 'server':3A,10A,31B,47B,55B,64C,86C,93C 'small':44B,80C 'use':73C 'x':2A,30B,41B,54B,63C,76C,85C,92C 'x.org':1A,29B,62C 'x11':21B 'xwayland':22B,35B,68C","nicknames":[],"mitigations":[],"who_affected":"Systems running X.Org X Server before 21.1.25 or XWayland before 24.1.14. The attacker must already be an authenticated X client on the display, so machines with no untrusted local X clients carry less risk. Wayland-only systems without XWayland are not affected by the XWayland part.","tier":"C","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-28T17:18:53+00:00","kev":null,"cvss_vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/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":"meissner@suse.de","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-93524","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-93524","severity":null,"published_at":"2026-10-28T17:18:53+00:00","modified_at":"2026-10-28T17:18:53+00:00","first_seen_at":"2026-10-28T17:34:10+00:00","fetched_at":"2026-10-28T17:34:10+00:00","note":null}],"documents":[],"notice":"Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai"}