{"id":"CVE-2026-119742","title":"Nagios XI < 2026R2 OS Command Injection via mibs.php","summary":"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 semico…","severity":"high","cvss":7.2,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H","cvssSource":"cna","cwe":["CWE-78"],"vendor":"Nagios Enterprises, LLC","product":"Nagios XI","affected":["nagios_xi < 2026R2"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-11-03T15:59:04.070564Z"},"published":"2026-11-03","updated":"2026-11-03","sourceUpdated":"2026-11-03T16:00:18.389Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-119742","references":[{"url":"https://www.nagios.com/security-disclosures/nagios-xi/2026r2/","label":"Release Notes"},{"url":"https://www.vulncheck.com/advisories/nagios-xi-2026r2-os-command-injection-via-mibs-php","label":"VulnCheck Advisory: Nagios XI < 2026R2 OS Command Injection via mibs.php"}],"tags":["cve.org"],"epss":0.04088,"epssPercentile":0.90788,"ingestedAt":"2026-11-05T20:33:06.278Z","slug":"CVE-2026-119742","body":"## Overview\n\nNagios 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.\n\n## Affected\n\n- `nagios_xi < 2026R2`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":40,"depthScoreParts":{"impact":39.6,"likelihood":0.8,"exploitation":0,"ransomware":0},"changes":[]}