Cisco IOS XR Software Enhanced Preboot eXecution Environment Unsigned Code Execution Vulnerability (Cisco Cisco IOS XR Software)
At a glance
- Source
- NVD
- EPSS
- EPSS 2.89 % · percentile 87 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- cisco
- NVD status
- Modified
Description
A vulnerability in the enhanced Preboot eXecution Environment (PXE) boot loader for Cisco IOS XR 64-bit Software could allow an unauthenticated, remote attacker to execute unsigned code during the PXE boot process on an affected device. The PXE boot loader is part of the BIOS and runs over the management interface of hardware platforms that are running Cisco IOS XR Software only. The vulnerability exists because internal commands that are issued when the PXE network boot process is loading a software image are not properly verified. An attacker could exploit this vulnerability by compromising the PXE boot server and replacing a valid software image with a malicious one. Alternatively, the attacker could impersonate the PXE boot server and send a PXE boot reply with a malicious file. A successful exploit could allow the attacker to execute unsigned code on the affected device. Note: To fix this vulnerability, both the Cisco IOS XR Software and the BIOS must be upgraded. The BIOS code is included in Cisco IOS XR Software but might require additional installation steps. For further information, see the Fixed Software section of this advisory.
Weaknesses (CWE)
- CWE-284 — Improper Access Control
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.0 | HIGH 8.1 | CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H | cisco |
| CVSS 3.1 | CRITICAL 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H | NVD · nvd@nist.gov (Primary) |
| CVSS 3.0 | HIGH 8.1 | CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H | NVD · psirt@cisco.com (Secondary) |
| CVSS 2.0 | HIGH 9.3 | AV:N/AC:M/Au:N/C:C/I:C/A:C | NVD · nvd@nist.gov (Primary) |
European references
- ENISA EUVD · EUVD-2020-24555
- GCVE · GCVE-0-2020-3284
CERT-FR advisories
- CERTFR-2020-AVI-713 — Multiples vulnérabilités dans les produits Cisco · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:o:cisco:a9k-rsp880-se_firmware:*:*:*:*:*:*:*:*< 10.65cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*< 6.5.2cpe:2.3:o:cisco:a9k-rsp880-tr_firmware:*:*:*:*:*:*:*:*< 10.65cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*< 6.5.2cpe:2.3:o:cisco:a99-rp2-se_firmware:*:*:*:*:*:*:*:*< 14.35cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*< 6.5.2cpe:2.3:o:cisco:a99-rp2-tr_firmware:*:*:*:*:*:*:*:*< 14.35cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*< 6.5.2cpe:2.3:o:cisco:a99-rsp-se_firmware:*:*:*:*:*:*:*:*< 16.14cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*< 6.5.2cpe:2.3:o:cisco:a99-rsp-tr_firmware:*:*:*:*:*:*:*:*< 16.14cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*< 6.5.2cpe:2.3:o:cisco:a9k-rsp880-lt-se_firmware:*:*:*:*:*:*:*:*< 17.34cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*< 6.5.2cpe:2.3:o:cisco:a9k-rsp880-lt-tr_firmware:*:*:*:*:*:*:*:*< 17.34cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*< 6.5.2cpe:2.3:o:cisco:asr-9901-rp_firmware:*:*:*:*:*:*:*:*< 22.20cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*< 6.5.2cpe:2.3:o:cisco:a99-rp3-se_firmware:*:*:*:*:*:*:*:*< 30.23cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*< 6.5.2cpe:2.3:o:cisco:a99-rp3-tr_firmware:*:*:*:*:*:*:*:*< 30.23cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*< 6.5.2cpe:2.3:o:cisco:a9k-rsp5-se_firmware:*:*:*:*:*:*:*:*< 31.20cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*< 6.5.2cpe:2.3:o:cisco:a9k-rsp5-tr_firmware:*:*:*:*:*:*:*:*< 31.20cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*< 6.5.2cpe:2.3:o:cisco:ncs1001_firmware:*:*:*:*:*:*:*:*< 14.60cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*< 6.5.2cpe:2.3:o:cisco:ncs1002_firmware:*:*:*:*:*:*:*:*< 14.60cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*< 6.5.2cpe:2.3:o:cisco:ncs1004_firmware:*:*:*:*:*:*:*:*< 14.60cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*< 6.5.2cpe:2.3:o:cisco:n540-12z20g-sys-a\/d_firmware:*:*:*:*:*:*:*:*< 1.15cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*< 7.2.1cpe:2.3:o:cisco:n540-24z8q2c-m_firmware:*:*:*:*:*:*:*:*< 1.15cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*< 6.5.2cpe:2.3:o:cisco:n540-28z4c-sys-a\/d_firmware:*:*:*:*:*:*:*:*< 1.15cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*< 6.5.2cpe:2.3:o:cisco:n540-acc-sys_firmware:*:*:*:*:*:*:*:*< 1.15cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*< 6.5.2- +50 more
Affected products
| Product | Versions |
|---|---|
| Cisco · Cisco IOS XR Software | affected n/a |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |