{"id":"CVE-2026-93519","kind":"vulnerability","aliases":["CVE-2026-93519"],"related":[],"title":"X.Org X server: XFIXES pointer barrier overflow lets clients crash or run code","description":"A buffer overflow when handling pointer barriers in the XFIXES extension in X.Org X server before 21.1.25 and XWayland before 24.1.14 could be used by authenticated X clients to crash or potentially execute code in X server context.","summary":"A buffer overflow in the XFIXES extension's pointer barrier handling in X.Org X server (before 21.1.25) and XWayland (before 24.1.14) can be triggered by an authenticated X client. An attacker can crash the X server or potentially execute code in its context.","severity":"high","cvss":7.8,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["infrastructure","linux-desktop","x.org","xorg-server","xwayland"],"not_affected_if":["no-x-server","patched-version"],"how_to_check":"- Run `Xorg -version` or `X -version` and compare against `21.1.25`.\n- For XWayland, run `Xwayland -version` and compare against `24.1.14`.\n- Check your distribution's package manager for the installed xorg-server or xwayland package version.","fix":"- Upgrade X.Org X server to `21.1.25` or later.\n- Upgrade XWayland to `24.1.14` or later.\n- Apply your distribution's xorg-server and xwayland security updates.","status":"open","published_at":"2026-10-28T15:17:10+00:00","first_seen_at":"2026-10-28T15:33:37+00:00","triaged_at":"2026-10-28T15:35:05+00:00","updated_at":"2026-10-28T15:35:05+00:00","category":"infrastructure","confidence":0.6,"triage":{"at":"2026-10-28T15:35:05Z","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.\n- Apply your distribution's xorg-server and xwayland security updates.","reach":"local","title":"X.Org X server: XFIXES pointer barrier overflow lets clients crash or run code","impact":"high","summary":"A buffer overflow in the XFIXES extension's pointer barrier handling in X.Org X server (before 21.1.25) and XWayland (before 24.1.14) can be triggered by an authenticated X client. An attacker can crash the X server or potentially execute code in its context.","category":"infrastructure","nicknames":[],"who_cares":["x.org","xwayland","linux-desktop","xorg-server"],"confidence":0.6,"needs_auth":"yes","worst_case":"Attacker crashes X server or runs code in its context","analyst_note":"Check the upstream X.Org security advisory for the exact affected version range and whether the code execution is practically reachable; sources gave only the NVD description.","how_to_check":"- Run `Xorg -version` or `X -version` and compare against `21.1.25`.\n- For XWayland, run `Xwayland -version` and compare against `24.1.14`.\n- Check your distribution's package manager for the installed xorg-server or xwayland package version.","needs_analyst":true,"not_affected_if":["no-x-server","patched-version"],"who_is_affected":"Systems running an X.Org X server older than 21.1.25 or XWayland older than 24.1.14 are exposed, since the flaw sits in the XFIXES extension that any X client can reach. Exposure requires a client that can connect to the X server, so multi-user desktops and hosts where untrusted local processes can reach the X display are the main concern. Headless hosts without an X server, and systems already on the fixed versions, can skip it.","user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"unknown"},"cost_usd":0.000669,"input_tokens":3300,"output_tokens":679,"severity_before":"high"},"analyst_status":null,"analyst_note":null,"search":"'-2026':15A,18A '-93519':16A,19A '21.1.25':45B,88C '24.1.14':49B,92C 'attack':59B 'authent':55B,97C 'barrier':6A,38B,78C 'buffer':30B,73C 'client':9A,57B,99C 'code':13A,68B,105C 'context':71B,109C 'could':93C 'crash':10A,61B,101C 'cve':14A,17A 'desktop':23B 'execut':67B,104C 'extens':35B,82C 'handl':39B,76C 'infrastructur':20B 'let':8A 'linux':22B 'linux-desktop':21B 'overflow':7A,31B,74C 'pointer':5A,37B,77C 'potenti':66B,103C 'run':12A 'server':3A,27B,43B,64B,86C,108C 'trigger':52B 'use':95C 'x':2A,42B,56B,63B,85C,98C,107C 'x.org':1A,24B,41B,84C 'xfix':4A,34B,81C 'xorg':26B 'xorg-serv':25B 'xwayland':28B,47B,90C","nicknames":[],"mitigations":[],"who_affected":"Systems running an X.Org X server older than 21.1.25 or XWayland older than 24.1.14 are exposed, since the flaw sits in the XFIXES extension that any X client can reach. Exposure requires a client that can connect to the X server, so multi-user desktops and hosts where untrusted local processes can reach the X display are the main concern. Headless hosts without an X server, and systems already on the fixed versions, can skip it.","tier":"B","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-28T15:17:10+00:00","kev":null,"cvss_vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cvss_by":"meissner@suse.de","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-93519","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-93519","severity":null,"published_at":"2026-10-28T15:17:10+00:00","modified_at":"2026-10-28T15:21:55+00:00","first_seen_at":"2026-10-28T15:33:37+00:00","fetched_at":"2026-10-28T15:33:37+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"}