# CVE-2025-20159: Cisco IOS XR Software Management Interface ACL Bypass Vulnerability

> Unauthenticated remote attackers can bypass management interface ACLs on Cisco IOS XR devices, exposing SSH, NetConf, and gRPC services.

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 10 Sep 2025
- **Updated:** 10 Sep 2025
- **Also known as:** GHSA-6rcj-394r-r32c

## What is CVE-2025-20159?

CVE-2025-20159 is a medium-severity vulnerability in Cisco IOS XR Software, published on 10 Sep 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability in the management interface access control list (ACL) processing feature in Cisco IOS XR Software could allow an unauthenticated, remote attacker to bypass configured ACLs for the SSH, NetConf, and gRPC features.

This vulnerability exists because management interface ACLs have not been supported on Cisco IOS XR Software Packet I/O infrastructure platforms for Linux-handled features such as SSH, NetConf, or gRPC. An attacker could exploit this vulnerability by attempting to send traffic to an affected device. A successful exploit could allow the attacker to bypass an ingress ACL that is applied on the management interface of the affected device.

Weakness: CWE-284 (Improper Access Control)

## Which versions are affected by CVE-2025-20159?


## How do I fix CVE-2025-20159?

No fix has been published for CVE-2025-20159 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-20159 being exploited?

There is no known exploitation of CVE-2025-20159 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-20159 and fix it if it is affected.

What it is: CVE-2025-20159 is a medium-severity vulnerability in Cisco IOS XR Software, published on 10 Sep 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-20159 in the wild and no public exploit code.

Affected product: Cisco IOS XR Software. 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-2025-20159/ (Markdown: https://insights.sbomify.com/CVE-2025-20159/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-20159
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-20159
- OSV: https://osv.dev/vulnerability/CVE-2025-20159

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-20159/
Summaries are generated and may contain mistakes; the official description above is the record.