# CVE-2025-61909: Icinga 2 signals sent as root to processes based on PID file written by the Icinga 2 daemon user

> A local attacker with Icinga daemon privileges can escalate to root by sending signals to arbitrary processes via a writable PID file.

- **Severity:** Medium 4.0 (`CVSS:4.0/AV:L/AC:L/AT:P/PR:H/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:H`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 16 Oct 2025
- **Updated:** 16 Oct 2025
- **Also known as:** DEBIAN-CVE-2025-61909, GHSA-pg6g-g99v-mw46, UBUNTU-CVE-2025-61909

## What is CVE-2025-61909?

CVE-2025-61909 is a medium-severity vulnerability in icinga2, published on 16 Oct 2025. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Icinga 2 is an open source monitoring system. From 2.10.0 to before 2.15.1, 2.14.7, and 2.13.13, the safe-reload script (also used during systemctl reload icinga2) and logrotate configuration shipped with Icinga 2 read the PID of the main Icinga 2 process from a PID file writable by the daemon user, but send the signal as the root user. This can allow the Icinga user to send signals to processes it would otherwise not permitted to. A fix is included in the following Icinga 2 versions: 2.15.1, 2.14.7, and 2.13.13.

Weakness: CWE-250 (Execution with Unnecessary Privileges)

## Which versions are affected by CVE-2025-61909?

It affects 1 product.


Products: Icinga Icinga.

## How do I fix CVE-2025-61909?

Upgrade to a fixed version.

## Is CVE-2025-61909 being exploited?

There is no known exploitation of CVE-2025-61909 in the wild and no public exploit code.

## Other vulnerabilities in icinga2

- [CVE-2025-48057](https://insights.sbomify.com/CVE-2025-48057/): Icinga 2 certificate renewal might incorrectly renew an invalid certificate (critical 9.3)
- [CVE-2020-29663](https://insights.sbomify.com/CVE-2020-29663/): Security feature bypass in n/a (critical 9.1)
- [CVE-2024-24820](https://insights.sbomify.com/CVE-2024-24820/): Icinga Director configuration is susceptible to Cross-Site Request Forgery (high 8.3)
- [CVE-2018-6535](https://insights.sbomify.com/CVE-2018-6535/): Information disclosure in n/a (high 8.1)
- [CVE-2020-14004](https://insights.sbomify.com/CVE-2020-14004/): Path traversal in n/a (high 7.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-61909 and fix it if it is affected.

What it is: CVE-2025-61909 is a medium-severity vulnerability in icinga2, published on 16 Oct 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-61909 in the wild and no public exploit code.

Affected product: icinga2. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2025-61909/ (Markdown: https://insights.sbomify.com/CVE-2025-61909/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-61909
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-61909
- OSV: https://osv.dev/vulnerability/CVE-2025-61909

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-61909/
Summaries are generated and may contain mistakes; the official description above is the record.