{"id":"CLSA-2026-1788373494","summary":"xorg-x11-server: Fix of 5 CVEs","details":"- CVE-2026-50257: fix use-after-free in miSyncDestroyFence() when a fence is destroyed while an Await group still references it\n- CVE-2026-50258: fix stack buffer overflow in XKB CheckKeyTypes() by rejecting key types whose numLevels exceeds XkbMaxShiftLevel\n- CVE-2026-50259: fix stack buffer overflow in XKB CheckKeyTypes() by clamping nMaps to the mapWidths buffer size\n- CVE-2026-50260: fix use-after-free in FreeCounter() when a SyncCounter is destroyed while an Await group still references it\n- CVE-2026-50261: fix use-after-free in SyncChangeCounter() by restarting trigger list iteration after a trigger fires","modified":"2026-10-26T09:31:58.731757428Z","published":"2026-09-02T18:25:07Z","upstream":["CVE-2026-50257","CVE-2026-50258","CVE-2026-50259","CVE-2026-50260","CVE-2026-50261"],"references":[{"type":"ADVISORY","url":"https://errata.tuxcare.com/els_os/rhel7els/CLSA-2026-1788373494.html"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-50257"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-50258"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-50259"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-50260"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-50261"}],"affected":[{"package":{"name":"xorg-x11-server-Xdmx","ecosystem":"TuxCare:RHEL:7","purl":"pkg:rpm/tuxcare/xorg-x11-server-Xdmx?distro=rhel-7"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.20.4-99.el7_9.tuxcare.els11"}]}],"database_specific":{"source":"https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/rhel7els/CLSA-2026-1788373494.json"}},{"package":{"name":"xorg-x11-server-Xephyr","ecosystem":"TuxCare:RHEL:7","purl":"pkg:rpm/tuxcare/xorg-x11-server-Xephyr?distro=rhel-7"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.20.4-99.el7_9.tuxcare.els11"}]}],"database_specific":{"source":"https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/rhel7els/CLSA-2026-1788373494.json"}},{"package":{"name":"xorg-x11-server-Xnest","ecosystem":"TuxCare:RHEL:7","purl":"pkg:rpm/tuxcare/xorg-x11-server-Xnest?distro=rhel-7"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.20.4-99.el7_9.tuxcare.els11"}]}],"database_specific":{"source":"https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/rhel7els/CLSA-2026-1788373494.json"}},{"package":{"name":"xorg-x11-server-Xorg","ecosystem":"TuxCare:RHEL:7","purl":"pkg:rpm/tuxcare/xorg-x11-server-Xorg?distro=rhel-7"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.20.4-99.el7_9.tuxcare.els11"}]}],"database_specific":{"source":"https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/rhel7els/CLSA-2026-1788373494.json"}},{"package":{"name":"xorg-x11-server-Xvfb","ecosystem":"TuxCare:RHEL:7","purl":"pkg:rpm/tuxcare/xorg-x11-server-Xvfb?distro=rhel-7"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.20.4-99.el7_9.tuxcare.els11"}]}],"database_specific":{"source":"https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/rhel7els/CLSA-2026-1788373494.json"}},{"package":{"name":"xorg-x11-server-Xwayland","ecosystem":"TuxCare:RHEL:7","purl":"pkg:rpm/tuxcare/xorg-x11-server-Xwayland?distro=rhel-7"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.20.4-99.el7_9.tuxcare.els11"}]}],"database_specific":{"source":"https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/rhel7els/CLSA-2026-1788373494.json"}},{"package":{"name":"xorg-x11-server-common","ecosystem":"TuxCare:RHEL:7","purl":"pkg:rpm/tuxcare/xorg-x11-server-common?distro=rhel-7"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.20.4-99.el7_9.tuxcare.els11"}]}],"database_specific":{"source":"https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/rhel7els/CLSA-2026-1788373494.json"}},{"package":{"name":"xorg-x11-server-devel","ecosystem":"TuxCare:RHEL:7","purl":"pkg:rpm/tuxcare/xorg-x11-server-devel?distro=rhel-7"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.20.4-99.el7_9.tuxcare.els11"}]}],"database_specific":{"source":"https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/rhel7els/CLSA-2026-1788373494.json"}},{"package":{"name":"xorg-x11-server-source","ecosystem":"TuxCare:RHEL:7","purl":"pkg:rpm/tuxcare/xorg-x11-server-source?distro=rhel-7"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.20.4-99.el7_9.tuxcare.els11"}]}],"database_specific":{"source":"https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/rhel7els/CLSA-2026-1788373494.json"}}],"schema_version":"1.9.0"}