{"id":"UBUNTU-CVE-2026-119742","details":"Nagios XI before 2026R2 contains an OS command injection vulnerability in the MIB upload feature where the install_mib() function in mibs.php sanitizes uploaded filenames with an incomplete character-substitution filter that omits semicolons, pipes, and non-space IFS whitespace characters before passing them to a grep command run via exec(). An authenticated administrator can upload a MIB file with a crafted filename using tab characters to bypass the deny-list and pipe to sh via a multipart POST request to mibs.php, resulting in arbitrary OS command execution as the web server user.","modified":"2026-11-05T11:47:26.681558567Z","published":"2026-11-03T14:17:00Z","upstream":["CVE-2026-119742"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-119742"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-119742"},{"type":"REPORT","url":"https://www.nagios.com/security-disclosures/nagios-xi/2026r2/"},{"type":"REPORT","url":"https://www.vulncheck.com/advisories/nagios-xi-2026r2-os-command-injection-via-mibs-php"}],"affected":[{"package":{"name":"nagios3","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/nagios3?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.5.1-1ubuntu4","3.5.1.dfsg-2ubuntu1","3.5.1.dfsg-2ubuntu2","3.5.1.dfsg-2.1ubuntu1","3.5.1.dfsg-2.1ubuntu1.1","3.5.1.dfsg-2.1ubuntu1.2","3.5.1.dfsg-2.1ubuntu1.3"],"ecosystem_specific":{"binaries":[{"binary_name":"nagios3","binary_version":"3.5.1.dfsg-2.1ubuntu1.3"},{"binary_version":"3.5.1.dfsg-2.1ubuntu1.3","binary_name":"nagios3-cgi"},{"binary_name":"nagios3-common","binary_version":"3.5.1.dfsg-2.1ubuntu1.3"},{"binary_name":"nagios3-core","binary_version":"3.5.1.dfsg-2.1ubuntu1.3"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-119742.json"}},{"package":{"name":"icinga","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/icinga?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.13.3-1","1.13.3-2","1.13.3-2ubuntu0.1"],"ecosystem_specific":{"binaries":[{"binary_version":"1.13.3-2ubuntu0.1","binary_name":"icinga"},{"binary_version":"1.13.3-2ubuntu0.1","binary_name":"icinga-cgi"},{"binary_name":"icinga-cgi-bin","binary_version":"1.13.3-2ubuntu0.1"},{"binary_name":"icinga-common","binary_version":"1.13.3-2ubuntu0.1"},{"binary_version":"1.13.3-2ubuntu0.1","binary_name":"icinga-core"},{"binary_name":"icinga-idoutils","binary_version":"1.13.3-2ubuntu0.1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-119742.json"}},{"package":{"name":"icinga","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/icinga?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.13.4-2build1"],"ecosystem_specific":{"binaries":[{"binary_name":"icinga","binary_version":"1.13.4-2build1"},{"binary_version":"1.13.4-2build1","binary_name":"icinga-cgi"},{"binary_name":"icinga-cgi-bin","binary_version":"1.13.4-2build1"},{"binary_version":"1.13.4-2build1","binary_name":"icinga-common"},{"binary_version":"1.13.4-2build1","binary_name":"icinga-core"},{"binary_version":"1.13.4-2build1","binary_name":"icinga-idoutils"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-119742.json"}},{"package":{"name":"nagios3","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/nagios3?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.5.1.dfsg-2.1ubuntu8"],"ecosystem_specific":{"binaries":[{"binary_name":"nagios3","binary_version":"3.5.1.dfsg-2.1ubuntu8"},{"binary_name":"nagios3-cgi","binary_version":"3.5.1.dfsg-2.1ubuntu8"},{"binary_name":"nagios3-common","binary_version":"3.5.1.dfsg-2.1ubuntu8"},{"binary_version":"3.5.1.dfsg-2.1ubuntu8","binary_name":"nagios3-core"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-119742.json"}},{"package":{"name":"nagios4","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/nagios4?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.3.4-3","4.3.4-3ubuntu0.1"],"ecosystem_specific":{"binaries":[{"binary_name":"nagios4","binary_version":"4.3.4-3ubuntu0.1"},{"binary_name":"nagios4-cgi","binary_version":"4.3.4-3ubuntu0.1"},{"binary_name":"nagios4-common","binary_version":"4.3.4-3ubuntu0.1"},{"binary_name":"nagios4-core","binary_version":"4.3.4-3ubuntu0.1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-119742.json"}},{"package":{"name":"nagios4","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/nagios4?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.4.6-4","4.4.6-4ubuntu0.22.04.1"],"ecosystem_specific":{"binaries":[{"binary_version":"4.4.6-4ubuntu0.22.04.1","binary_name":"nagios4"},{"binary_version":"4.4.6-4ubuntu0.22.04.1","binary_name":"nagios4-cgi"},{"binary_name":"nagios4-common","binary_version":"4.4.6-4ubuntu0.22.04.1"},{"binary_version":"4.4.6-4ubuntu0.22.04.1","binary_name":"nagios4-core"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-119742.json"}},{"package":{"name":"nagios4","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/u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