Predictive Vulnerability Intelligence.

Product

  • Product
  • Pricing
  • Documentation

Company

  • About
  • Partnerships
  • Blog
  • Support

Legal

  • Terms
  • Privacy
  • Data Licensing

© 2026 FAUCET Technologies LLC. All rights reserved.

CVE-2020-3455

20
FAUCET Score

CVE-2020-3455 is a high-severity vulnerability in Cisco FXOS Software that allows an authenticated, local attacker to bypass secure boot mechanisms. By injecting code into a specific file, an attacker can break the chain of trust, inject persistent malicious code into the boot process, and achieve full compromise of the device. Despite its high CVSS score of 7.8, there is currently no public exploit code available, and it has not been added to CISA's Known Exploited Vulnerabilities catalog. Community discussion and media coverage for this CVE are minimal, suggesting low public awareness or active exploitation.

Impacted Technologies

VendorProductVersion(s)CPE
< 2.4.1.268CPE matchmatch criteria
cpe:2.3:o:cisco:firepower_extensible_operating_system:*:*:*:*:*:*:*:*
>= 2.6, < 2.6.1.214CPE matchmatch criteria
cpe:2.3:o:cisco:firepower_extensible_operating_system:*:*:*:*:*:*:*:*
>= 2.7, < 2.7.1.131CPE matchmatch criteria
cpe:2.3:o:cisco:firepower_extensible_operating_system:*:*:*:*:*:*:*:*

CVSS Data

CVSS version used by this source: 3.0

6.7MEDIUM

CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
HIGH
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
Exploitability Score
0.8
Impact Score
5.9
CvssVersion
3.0

Exploit Intelligence

EPSS Score
0.35%
Probability of exploitation in next 30 days
EPSS Percentile
27.4%
Percentile rank of EPSS score among Peer Group
As of 2026-07-27
Model: v2026.06.15
This CVE's current EPSS score of 0.0035 is in the 66th percentile among its peer group of 17,070 CVEs.

Social Chatter

No social media mentions found for this CVE.

The average CVE in this peer group has 0.0 Twitter, 0.1 Reddit, 0.2 Bluesky, 0.1 Mastodon, and 0.2 GitHub mentions.

Media Mentions

No media coverage found for this CVE.

The average CVE in this peer group has 0.3 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Patch Available

Vendor Patches (1)

ciscopatch availablevia nvd_reference
View patch

References

tools.cisco.com / security/center/content/CiscoSecurityAdvisory/cisco-sa-fxos-sbbp-XTuPkYTn
PatchVendor Advisory