# CVE-2026-48549: nagios4: Nagios Core before 4.5.13 and Nagios XI before 2026R1.5 contains a CSRF vulnerability in cmd.cgi

CVE-2026-48549 is fixed in nagios4 on 1 platform, first by DEBIAN-CVE-2026-48549, released August 26, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-48549
- Priority: Routine
- CVSS: n/a
- EPSS: 0.0026
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Aug 26, 2026

## Description

Nagios Core before 4.5.13 and Nagios XI before 2026R1.5 contains a CSRF vulnerability in cmd.cgi. When no Cookie header is present, the double-submit cookie protection can be bypassed by supplying matching NagFormId and nagFormId values in the POST body, allowing a cross-site request to execute Nagios commands as a currently authenticated user.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | nagios4 Debian 12.15 (bookworm) | 4.4.6-4+deb12u2 | [DEBIAN-CVE-2026-48549](https://patchblox.com/security/data/fix/linux/debian-cve-2026-48549.md) | Aug 26, 2026 |
| Linux | nagios4 Debian 13.5 (trixie) | 4.4.6-4.1+deb13u2 | [DEBIAN-CVE-2026-48549](https://patchblox.com/security/data/fix/linux/debian-cve-2026-48549.md) | Aug 26, 2026 |
| Linux | nagios4 Debian 14 | 4.5.14+ds-1 | [DEBIAN-CVE-2026-48549](https://patchblox.com/security/data/fix/linux/debian-cve-2026-48549.md) | Aug 26, 2026 |

---

Data as of 2026-11-08T13:06:02Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

Free to use with attribution: show "Data: Patchblox Patch Radar" with a link to https://patchblox.com/security/patch-radar. Terms, including what needs a written agreement: https://patchblox.com/security/patch-radar/use-the-data

Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.