{"id":"CVE-2019-20794","title":"An issue was discovered in the Linux kernel 4.18 through 5.6.11 when unprivileged user namespaces are allowed","summary":"An issue was discovered in the Linux kernel 4.18 through 5.6.11 when unprivileged user namespaces are allowed. A user can create their own PID namespace, and mount a FUSE filesystem. Upon interaction with this FUSE filesystem, if the use…","severity":"medium","cvss":4.7,"cvssVector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-772"],"vendor":"linux","product":"linux_kernel","affected":["linux_kernel >= 4.18, <= 5.6.11"],"published":"2020-05-09","updated":"2026-10-08","sourceUpdated":"2026-10-08T21:17:19.947","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2019-20794","references":[{"url":"http://www.openwall.com/lists/oss-security/2020/08/24/1","label":"cve@mitre.org"},{"url":"https://github.com/sargun/fuse-example","label":"cve@mitre.org"},{"url":"https://security.netapp.com/advisory/ntap-20200608-0001/","label":"cve@mitre.org"},{"url":"https://sourceforge.net/p/fuse/mailman/message/36598753/","label":"cve@mitre.org"},{"url":"http://www.openwall.com/lists/oss-security/2020/08/24/1","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/sargun/fuse-example","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.netapp.com/advisory/ntap-20200608-0001/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://sourceforge.net/p/fuse/mailman/message/36598753/","label":"af854a3a-2127-422b-91ae-364da2661108"}],"tags":["nvd"],"epss":0.00512,"epssPercentile":0.41794,"ingestedAt":"2026-10-08T22:11:53.714Z","slug":"CVE-2019-20794","body":"## Overview\n\nAn issue was discovered in the Linux kernel 4.18 through 5.6.11 when unprivileged user namespaces are allowed. A user can create their own PID namespace, and mount a FUSE filesystem. Upon interaction with this FUSE filesystem, if the userspace component is terminated via a kill of the PID namespace's pid 1, it will result in a hung task, and resources being permanently locked up until system reboot. This can result in resource exhaustion.\n\n## Affected\n\n- `linux_kernel >= 4.18, <= 5.6.11`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":26,"depthScoreParts":{"impact":25.9,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}