{"id":"CVE-2026-23920","title":"Host and event action script input is validated with a regex (set by the administrator), but the validation runs in multiline mode","summary":"Host and event action script input is validated with a regex (set by the administrator), but the validation runs in multiline mode. If ^ and $ anchors are used in user input validation, an injected newline lets authenticated users bypass…","severity":"high","cvss":8.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-78"],"vendor":"zabbix","product":"zabbix","affected":["zabbix >= 7.0.0, < 7.0.22","zabbix >= 7.2.0, < 7.2.15","zabbix >= 7.4.0, < 7.4.6"],"patched":["zabbix 7.4.6"],"published":"2026-03-24","updated":"2026-09-10","sourceUpdated":"2026-09-10T21:15:39.950","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-23920","references":[{"url":"https://support.zabbix.com/browse/ZBX-27639","label":"security@zabbix.com"}],"tags":["nvd"],"epss":0.00297,"epssPercentile":0.22524,"ingestedAt":"2026-09-10T22:07:00.624Z","slug":"CVE-2026-23920","body":"## Overview\n\nHost and event action script input is validated with a regex (set by the administrator), but the validation runs in multiline mode. If ^ and $ anchors are used in user input validation, an injected newline lets authenticated users bypass the check and inject shell commands.\n\n## Affected\n\n- `zabbix >= 7.0.0, < 7.0.22`\n- `zabbix >= 7.2.0, < 7.2.15`\n- `zabbix >= 7.4.0, < 7.4.6`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `zabbix 7.4.6`","depth":"twilight","depthScore":48,"depthScoreParts":{"impact":48.4,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}