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 the check and inject shell commands.
Metrics
Affected Vendors & Products
Advisories
No advisories yet.
Fixes
Solution
Update the affected components to their respective fixed versions.
Workaround
It is possible to use \A and \z anchors in the regex validation as a workaround.
References
| Link | Providers |
|---|---|
| https://support.zabbix.com/browse/ZBX-27639 |
|
History
Tue, 24 Mar 2026 19:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | 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 the check and inject shell commands. | |
| Title | Host and event action script regex validation can be bypassed in certain situations, leading to potential command injection | |
| Weaknesses | CWE-78 | |
| References |
| |
| Metrics |
cvssV4_0
|
Projects
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Status: PUBLISHED
Assigner: Zabbix
Published:
Updated: 2026-03-24T18:27:52.882Z
Reserved: 2026-01-19T14:02:54.327Z
Link: CVE-2026-23920
No data.
Status : Received
Published: 2026-03-24T19:16:49.557
Modified: 2026-03-24T19:16:49.557
Link: CVE-2026-23920
No data.
OpenCVE Enrichment
No data.
Weaknesses