{"id":"UBUNTU-CVE-2019-6293","details":"An issue was discovered in the function mark_beginning_as_normal in nfa.c in flex 2.6.4. There is a stack exhaustion problem caused by the mark_beginning_as_normal function making recursive calls to itself in certain scenarios involving lots of '*' characters. Remote attackers could leverage this vulnerability to cause a denial-of-service.","modified":"2026-05-20T16:03:59.119092035Z","published":"2019-01-15T00:29:00Z","upstream":["CVE-2019-6293"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2019-6293"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2019-6293"}],"affected":[{"package":{"name":"flex","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/flex?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.5.39-8","2.6.0-1","2.6.0-3","2.6.0-4","2.6.0-6","2.6.0-7","2.6.0-8","2.6.0-9","2.6.0-11"],"ecosystem_specific":{"binaries":[{"binary_version":"2.6.0-11","binary_name":"flex"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2019/UBUNTU-CVE-2019-6293.json"}},{"package":{"name":"flex","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/flex?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.6.1-1.3","2.6.4-1","2.6.4-2","2.6.4-3","2.6.4-4","2.6.4-5","2.6.4-6"],"ecosystem_specific":{"binaries":[{"binary_version":"2.6.4-6","binary_name":"flex"},{"binary_version":"2.6.4-6","binary_name":"libfl2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2019/UBUNTU-CVE-2019-6293.json"}},{"package":{"name":"flex","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/flex?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.6.4-6.2"],"ecosystem_specific":{"binaries":[{"binary_version":"2.6.4-6.2","binary_name":"flex"},{"binary_version":"2.6.4-6.2","binary_name":"libfl2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2019/UBUNTU-CVE-2019-6293.json"}},{"package":{"name":"flex","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/flex?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.6.4-8build1","2.6.4-8build2"],"ecosystem_specific":{"binaries":[{"binary_version":"2.6.4-8build2","binary_name":"flex"},{"binary_version":"2.6.4-8build2","binary_name":"libfl2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2019/UBUNTU-CVE-2019-6293.json"}},{"package":{"name":"flex","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/flex?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.6.4-8.2","2.6.4-8.2build1"],"ecosystem_specific":{"binaries":[{"binary_version":"2.6.4-8.2build1","binary_name":"flex"},{"binary_version":"2.6.4-8.2build1","binary_name":"libfl2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2019/UBUNTU-CVE-2019-6293.json"}},{"package":{"name":"flex","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/flex?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.6.4-8.2build1"],"ecosystem_specific":{"binaries":[{"binary_version":"2.6.4-8.2build1","binary_name":"flex"},{"binary_version":"2.6.4-8.2build1","binary_name":"libfl2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2019/UBUNTU-CVE-2019-6293.json"}},{"package":{"name":"flex","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/flex?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.6.4-8.2build1","2.6.4-8.2build2"],"ecosystem_specific":{"binaries":[{"binary_version":"2.6.4-8.2build2","binary_name":"flex"},{"binary_version":"2.6.4-8.2build2","binary_name":"libfl2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2019/UBUNTU-CVE-2019-6293.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"low"}]}