{"id":"CVE-2023-6546","title":"A race condition was found in the GSM 0710 tty multiplexor in the Linux kernel","summary":"A race condition was found in the GSM 0710 tty multiplexor in the Linux kernel. This issue occurs when two threads execute the GSMIOC_SETCONF ioctl on the same tty file descriptor with the gsm line discipline enabled, and can lead to a u…","severity":"high","cvss":7,"cvssVector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-366","CWE-362"],"vendor":"linux","product":"linux_kernel","affected":["linux_kernel < 6.5","linux_kernel = 6.5","fedora = 39","enterprise_linux = 8.0","enterprise_linux = 9.0"],"patched":["linux_kernel 6.5"],"published":"2023-12-21","updated":"2026-08-06","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2023-6546","references":[{"url":"https://access.redhat.com/errata/RHSA-2024:0930","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2024:0937","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2024:1018","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2024:1019","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2024:1055","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2024:1250","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2024:1253","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2024:1306","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2024:1607","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2024:1612","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2024:1614","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2024:2093","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2024:2394","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2024:2621","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2024:2697","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2024:4577","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2024:4729","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2024:4731","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2024:4970","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/security/cve/CVE-2023-6546","label":"secalert@redhat.com"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2255498","label":"secalert@redhat.com"},{"url":"https://github.com/torvalds/linux/commit/3c4f8333b582487a2d1e02171f1465531cde53e3","label":"secalert@redhat.com"},{"url":"https://www.zerodayinitiative.com/advisories/ZDI-CAN-20527","label":"secalert@redhat.com"},{"url":"http://www.openwall.com/lists/oss-security/2024/04/10/18","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.openwall.com/lists/oss-security/2024/04/10/21","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.openwall.com/lists/oss-security/2024/04/11/7","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.openwall.com/lists/oss-security/2024/04/11/9","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.openwall.com/lists/oss-security/2024/04/12/1","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.openwall.com/lists/oss-security/2024/04/12/2","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.openwall.com/lists/oss-security/2024/04/16/2","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.openwall.com/lists/oss-security/2024/04/17/1","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2024:0930","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2024:0937","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2024:1018","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2024:1019","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2024:1055","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2024:1250","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2024:1253","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2024:1306","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2024:1607","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2024:1612","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2024:1614","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2024:2093","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2024:2394","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2024:2621","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2024:2697","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2024:4577","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2024:4729","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2024:4731","label":"af854a3a-2127-422b-91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Overview\n\nA race condition was found in the GSM 0710 tty multiplexor in the Linux kernel. This issue occurs when two threads execute the GSMIOC_SETCONF ioctl on the same tty file descriptor with the gsm line discipline enabled, and can lead to a use-after-free problem on a struct gsm_dlci while restarting the gsm mux. This could allow a local unprivileged user to escalate their privileges on the system.\n\n## Affected\n\n- `linux_kernel < 6.5`\n- `linux_kernel = 6.5`\n- `fedora = 39`\n- `enterprise_linux = 8.0`\n- `enterprise_linux = 9.0`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `linux_kernel 6.5`","depth":"abyssal","depthScore":64,"depthScoreParts":{"impact":38.5,"likelihood":0.1,"exploitation":25,"ransomware":0},"changes":[{"seq":4671,"id":"CVE-2023-6546","ts":1788887198112,"field":"exploit_available","old":"false","new":"true"},{"seq":3554,"id":"CVE-2023-6546","ts":1788886314289,"field":"exploit_available","old":"true","new":"false"},{"seq":2408,"id":"CVE-2023-6546","ts":1788882983502,"field":"exploit_available","old":"false","new":"true"},{"seq":1437,"id":"CVE-2023-6546","ts":1788882396465,"field":"exploit_available","old":"true","new":"false"},{"seq":551,"id":"CVE-2023-6546","ts":1788881832793,"field":"exploit_available","old":"false","new":"true"}]}