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Vulnerability · CVE-2025-20155

A vulnerability in the bootstrap loading of Cisco IOS XE Software could allow an authenticated, local attacker to write arbitrary files to an affected system.

Published May 7, 2025 · corrected/updated Feb 26, 2026 · Cisco Cisco IOS XE Software · evidence confidence high

A vulnerability in the bootstrap loading of Cisco IOS XE Software could allow an authenticated, local attacker to write arbitrary files to an affected system. This vulnerability is due to insufficient input validation of the bootstrap file that is read by the system software when a device is first deployed in SD-WAN mode or when an administrator configures SD-Routing on the device. An attacker could exploit this vulnerability by modifying a bootstrap file generated by Cisco Catalyst SD-WAN Manager, loading it into the device flash, and then either reloading the device in a green field deployme

Grounded briefings

Catalog interpretations for three audiences. Each brief cites ingested metadata and the original advisories below. They are not independent research and they do not invent exploit steps.

Executive

CVE-2025-20155 is a medium public vulnerability record for Cisco Cisco IOS XE Software. It is not currently listed in the CISA Known Exploited catalog. Check the linked vendor or CERT advisories for patch status. This summary is a catalog interpretation of the ingested metadata and cites the original advisories below.

System administrator

Identify whether Cisco Cisco IOS XE Software is in your estate, then compare installed versions with the affected ranges. Affected packages or ranges on record: Cisco Cisco IOS XE Software 17.9.5a (17.9.5a). Check the linked vendor or CERT advisories for patch status. Prefer the vendor or distribution advisory linked in Sources before changing production systems. This is a catalog interpretation, not a runbook.

Security analyst

Signals on file: CVSS 6.0, EPSS 17.0%. It is not currently listed in the CISA Known Exploited catalog. Sources contributing to this record: cve_org, euvd. Public exploit references, when present, are outbound links only and are not proof of active exploitation. This is a catalog interpretation of stored metadata.

Exploitation and remediation

  • Exploitation evidence

    Not listed as known exploited in CISA KEV. Not in CISA KEV or VulnCheck KEV.

  • Patch and remediation

    No required-action text is stored yet. Use the vendor or CERT links in Sources for patch availability.

  • Safe detection guidance

    Compare installed versions with the affected ranges below and verify the advisory from the original publisher. This site stores metadata and outbound links only; it does not ship exploit code or proof-of-concept payloads.

Technology hubs

Cisco

Code

The project this record applies to. Exploit listings stay in References.

No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

  1. May 7, 2025 · EUVD

    Detected

    A vulnerability in the bootstrap loading of Cisco IOS XE Software could allow an authenticated, local attacker to write arbitrary files to an affected system. This vulnerability is due to insufficient input validation of the bootstrap file that is read by the system software when a device is first deployed in SD-WAN mode or when an administrator configures SD-Routing on the device. An attacker cou

  2. Feb 26, 2026 · EUVD

    Updated

    A vulnerability in the bootstrap loading of Cisco IOS XE Software could allow an authenticated, local attacker to write arbitrary files to an affected system. This vulnerability is due to insufficient input validation of the bootstrap file that is read by the system software when a device is first deployed in SD-WAN mode or when an administrator configures SD-Routing on the device. An attacker cou

Affected

  • vendor Cisco Cisco IOS XE Software 17.9.5a17.9.5a

Sources

  • CVE.orgVulnerability recordCVE-2025-20155

    Official CVE identifier

    cve.org
  • EUVDVulnerability recordEUVD-2025-13899

    A vulnerability in the bootstrap loading of Cisco IOS XE Software could allow an authenticated, local attacker to write arbitrary files to an affected system. This vulnerability is due to insufficient input validation of the bootstrap file that is read by the system software when

    euvd.enisa.europa.eu

References