Vulnerability report

Exploited in the wild Confirmed confidence In CISA KEV

CVE-2026-20131

Cisco Secure Firewall Management Center (FMC) Remote Code Execution

Cisco Secure Firewall Management Center (FMC) · 7.0.0

Watch CVE-2026-20131 Browse KEV feed
Severity
CVSS 10.0 · Critical
Confidence
Confirmed
Exploit status
Exploited in the wild
EPSS
43.2%
First observed
—
Last observed
—

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2026-20131 is an unauthenticated vulnerability affecting Cisco Secure Firewall Management Center (FMC). A vulnerability in the web-based management interface of Cisco Secure Firewall Management Center (FMC)...

Is it exploited?

Yes. Previdian tracks this CVE as a known exploited vulnerability. Confidence is confirmed. Listed in CISA KEV. Also confirmed by third-party sources.

Who is affected?

Cisco Secure Firewall Management Center (FMC) 7.0.0.

What should we do?

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

Overview

Cisco Secure Firewall Management Center (FMC) Remote Code Execution

A vulnerability in the web-based management interface of Cisco Secure Firewall Management Center (FMC) Software could allow an unauthenticated, remote attacker to execute arbitrary Java code as root on an affected device. This vulnerability is due to insecure deserialization of a user-supplied Java byte stream. An attacker could exploit this vulnerability by sending a crafted serialized Java object to the web-based management interface of an affected device.

A successful exploit could allow the attacker to execute arbitrary code on the device and elevate privileges to root. Note: If the FMC management interface does not have public internet access, the attack surface that is associated with this vulnerability is reduced.

Cisco Affected
Cisco Secure Firewall Management Center (FMC)
7.0.0 7.0.0.1 7.0.1 7.1.0 6.4.0.13 7.0.1.1 6.4.0.14 7.1.0.1 7.0.2 6.4.0.15 7.2.0 7.0.2.1 7.0.3 7.1.0.2 7.2.0.1 7.0.4 7.2.1 7.0.5 6.4.0.16 7.3.0 7.2.2 7.3.1 7.2.3 7.1.0.3 7.2.3.1 7.2.4 7.0.6 7.2.4.1 7.2.5 7.3.1.1 7.4.0 6.4.0.17 7.0.6.1 7.2.5.1 7.4.1 7.2.6 7.4.1.1 7.0.6.2 6.4.0.18 7.2.7 7.2.5.2 7.3.1.2 7.2.8 7.6.0 7.4.2 7.2.8.1 7.0.6.3 7.4.2.1 7.2.9 7.0.7 7.7.0 7.4.2.2 7.2.10 7.6.1 7.4.2.3 7.0.8 7.6.2 7.7.10 7.2.10.1 7.0.8.1 7.6.2.1 7.2.10.2 7.7.10.1 7.4.2.4 7.4.3 7.7.11 7.6.4 10.0.0 7.4.4 7.4.5
Published
04 Mar 2026
Exploitation Reported
01 Jun 2026
Attack vector
Remote
Complexity
Low
Privileges
None
User interaction
None

Tags

cisa edge malware

CVE References

  • CVE Record CVE.org · CVE Record https://www.cve.org/CVERecord?id=CVE-2026-20131
  • cisco-sa-fmc-rce-NKhnULJh sec.cloudapps.cisco.com · CVE Record https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurity...

Exploitation evidence

Why Previdian 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

CVE

Recorded 01 Jun 2026

A trusted third party reported exploitation.

Used in malware

CVE

Recorded 02 Jun 2026

Malware families have been linked to exploitation of this CVE.

Known exploited vulnerability sources

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

Learn about Pro API access
Source Added
CVE First 2026-06-01 12:10 UTC
CISA 2026-06-02 14:02 UTC

Detection

Operational artifacts and observed signals

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

Observed signals

Request targets
User-Agents
Callback hosts
0
0
0

Request targets and User-Agents available in Pro. Callback host details available in Enterprise.

Scanner coverage

No scanner integrations recorded yet.

Virtual patch status

No Previdian 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

10.0 Critical

Potential damage if exploited. Separate from whether attackers are using it.

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

EPSS

43.2%

Estimated chance of exploitation in the next 30 days. Previdian's warning comes from evidence, not this score.

Weaknesses

Deserialization of Untrusted Data CWE-502

Recent mention · NCSC Security Advisories

NCSC-2026-0076 [1.03] [H/H] Kwetsbaarheden verholpen in Cisco Secure Firewall Management Center

Cisco heeft kwetsbaarheden verholpen in Cisco Secure Firewall Management Center. De kwetsbaarheid met kenmerk CVE-2026-20079 bevindt zich in de webinterface van Cisco Secure Firewall Management Center. Een ongeauthenticeerde externe kwaadwillende kan de authenticatiecontroles...

Read full advisory

All Mentions

Recent mention · NCSC Security Advisories

NCSC-2026-0076 [1.03] [H/H] Kwetsbaarheden verholpen in Cisco Secure Firewall Management Center

NCSC Security Advisories · 12 Sep 2026

Cisco heeft kwetsbaarheden verholpen in Cisco Secure Firewall Management Center. De kwetsbaarheid met kenmerk CVE-2026-20079 bevindt zich in de webinterface van Cisco Secure Firewall Management Center. Een ongeauthenticeerde externe kwaadwillende kan de authenticatiecontroles omzeilen door een onjuist systeemproces dat bij het opstarten is aangemaakt te misbruiken. De kwaadwillende kan deze kwetsbaarheid misbruiken door speciaal geprepareerde HTTP-verzoeken naar een getroffen apparaat te sturen. Een succesvolle exploit kan de aanvaller in staat stellen verschillende scripts en commando’s...

Recent mention · NCSC Security Advisories

NCSC-2026-0076 [1.02] [H/H] Kwetsbaarheden verholpen in Cisco Secure Firewall Management Center

NCSC Security Advisories · 11 Sep 2026

Cisco heeft kwetsbaarheden verholpen in Cisco Secure Firewall Management Center. De kwetsbaarheid met kenmerk CVE-2026-20079 bevindt zich in de webinterface van Cisco Secure Firewall Management Center. Een ongeauthenticeerde externe kwaadwillende kan de authenticatiecontroles omzeilen door een onjuist systeemproces dat bij het opstarten is aangemaakt te misbruiken. De kwaadwillende kan deze kwetsbaarheid misbruiken door speciaal geprepareerde HTTP-verzoeken naar een getroffen apparaat te sturen. Een succesvolle exploit kan de aanvaller in staat stellen verschillende scripts en commando’s...

Timeline

From disclosure to observed exploitation

  1. 14:02 UTC

    First public exploitation report

    Exploit observed in malware

  2. 14:02 UTC

    Added to CISA KEV

    Listed in the CISA Known Exploited Vulnerabilities catalog

  3. 12:10 UTC

    Added to Previdian KEV Feed

    High-confidence, third-party attested exploitation

  4. 17:17 UTC

    CVE published

    Vulnerability disclosed publicly

  5. 11:59 UTC

    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.

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

GET /api/v2/pro/kevs/CVE-2026-20131

Free JSON includes basic KEV fields 
{
  "cve_id": "CVE-2026-20131",
  "confidence": "Confirmed",
  "cvss_score": 10.0,
  "cvss_estimated": false,
  "epss_score": 0.43166,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": false
  },
  "sensor_telemetry": { "attempts": 0, "sensors": 0 }
}