Vulnerability report

Exploited in the wild Confirmed confidence In CISA KEV

CVE-2013-3900

WinVerifyTrust Signature Validation Vulnerability

Microsoft / Windows 10 Version 1809

Severity
CVSS 5.5 · Medium
Confidence
Confirmed
Exploit status
Exploited in the wild
EPSS
44.6%
First observed
Last observed

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2013-3900 is an unauthenticated WinVerifyTrust Signature Validation Vulnerability affecting Microsoft Windows 10 Version 1809 and 27 other products. Why is Microsoft republishing a CVE from 2013? We are...

Is it exploited?

Yes. KEV Intelligence tracks this CVE as a known exploited vulnerability. Confidence is confirmed.

Who is affected?

Microsoft / Windows 10 Version 1809.

What should we do?

Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.

Overview

Why is Microsoft republishing a CVE from 2013?

Why is Microsoft republishing a CVE from 2013? We are republishing CVE-2013-3900 in the Security Update Guide to update the Security Updates table and to inform customers that the EnableCertPaddingCheck is available in all currently supported versions of Windows 10 and Windows 11. While the format is different from the original CVE published in 2013, except for clarifications about how to configure the EnableCertPaddingCheck registry value, the information herein remains unchanged from the original text published on December 10, 2013, Microsoft does not plan to enforce the stricter verification behavior as a default functionality on supported releases of Microsoft Windows. This behavior remains available as an opt-in feature via reg key setting, and is available on supported editions of Windows released since December 10, 2013. This includes all currently supported versions of Windows 10 and Windows 11. The supporting code for this reg key was incorporated at the time of release for Windows 10 and Windows 11, so no security update is required; however, the reg key must be set. See the Security Updates table for the list of affected software. Vulnerability Description A remote code execution vulnerability exists in the way that the WinVerifyTrust function handles Windows Authenticode signature verification for portable executable (PE) files. An anonymous attacker could exploit the vulnerability by modifying an existing signed executable file to leverage unverified portions of the file in such a way as to add malicious code to the file without invalidating the signature.

An attacker who successfully exploited this vulnerability could take complete control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. If a user is logged on with administrative user rights, an attacker who successfully exploited this vulnerability could take complete control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights. Exploitation of this vulnerability requires that a user or application run or install a specially crafted, signed PE file. An attacker could modify an... See more at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2013-3900

View vendor advisory (opens in new tab)
Published
11 Dec 2013
Exploitation Reported
10 Jan 2022
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
Required

Tags

windows microsoft cisa

CVE References

Exploitation evidence

Why KEV Intelligence marks this CVE as exploited

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploited in the wild

CISA

Recorded 10 Jan 2022

Independent exploitation attestation added to the KEV Intelligence record.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the KEV Intelligence Pro API.

Learn about Pro API access
Source Added
CISA First 2022-01-10 00:00 UTC
Tenable Blog 2026-06-02 14:21 UTC

Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Observed signals

Request targets
0
User-Agents
0

Raw values available in Pro and Enterprise.

Scanner coverage

No scanner integrations recorded yet.

Virtual patch status

No KEV Intelligence virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.

Learn about virtual patches →

No detection artifacts or sensor request patterns are available for this CVE yet.

Check back as sensor telemetry and scanner integrations are updated.

Risk and context

Severity, weaknesses, and research context

CVSS v3.1

5.5 Medium
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N

EPSS

44.6%

Recent mention · Tenable Blog

Inside the customer environment: Where threat actors, vulnerabilities, and exposed assets intersect

Tenable Research has developed a graph-based model linking 600+ threat groups to real-world customer exposures. It reveals which vulnerabilities sit at the intersection of severity, active exploitation, and organizational risk.Key takeawaysThe "patch everything" strategy is...

Read full advisory

All CVSS Scores

CVSS v3.1 5.5 Medium

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N

CVSS v2.0 7.6 High

AV:N/AC:H/Au:N/C:C/I:C/A:C

Timeline

From disclosure to observed exploitation

  1. KEV confirmed by Tenable Blog

    Exploitation attested by an external source

  2. Added to CISA KEV

    Listed in the CISA Known Exploited Vulnerabilities catalog

  3. CVE published

    Vulnerability disclosed publicly

  4. CVE ID reserved

    Identifier reserved by the CNA

Pro API

Automate this intelligence

Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

  • Evidence confidence and provenance
  • First-party sensor telemetry
  • PoC and scanner references
  • Affected versions and enrichment
  • Automation-ready JSON delivery

GET /api/v2/pro/kevs/CVE-2013-3900

Free JSON includes basic KEV fields
{
  "cve_id": "CVE-2013-3900",
  "confidence": "Confirmed",
  "cvss_score": 5.5,
  "cvss_estimated": false,
  "epss_score": 0.44647,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": false
  },
  "sensor_telemetry": { "attempts": 0, "sensors": 0 }
}

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