CVE-2025-53843: Stack buffer overflow in CAPWAP daemon

Published Nov 18, 2025
·
Updated

A stack-based buffer overflow vulnerability in Fortinet FortiOS 7.6.0 through 7.6.3, FortiOS 7.4.0 through 7.4.8, FortiOS 7.2 all versions, FortiOS 7.0 all versions, FortiOS 6.4 all versions allows attacker to execute unauthorized code or commands via specially crafted packets

Other sources

A stack-based overflow vulnerability [CWE-124] in FortiOS and FortiSwitchManager CAPWAP daemon may allow a remote authenticated attacker to execute arbitrary code or command as a low privileged user via specially crafted packets.Successful exploitation would require a large amount of effort in preparation because of stack protection and ASLR. Additionally, attacker must be able to pose as an authorized FortiAP or FortiExtender.

— FortiGuard

Affected Software

8 affected componentsFixes available
Fortinet FortiOS>=7.6.0<=7.6.3, >=7.4.0<7.4.9, >=7.2, >=7.0, >=6.4
Fortinet FortiOS>=7.6.0<=7.6.3
Fortinet FortiOS>=7.4.0<=7.4.8
Fortinet FortiOS>=7.2
Fortinet FortiOS>=7.0
Fortinet FortiOS>=6.4
Fortinet FortiOS>=6.4.0<7.4.9
Fortinet FortiOS>=7.6.0<7.6.4

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade FortiOS to a version that resolves this vulnerability.

    Fixed in 7.4.9
  2. Upgrade

    Upgrade FortiOS to a version that resolves this vulnerability.

    Fixed in 7.6.4
  3. Upgrade

    Upgrade FortiSwitchManager to a version that resolves this vulnerability.

    Fixed in 7.0.6
  4. Upgrade

    Upgrade FortiSwitchManager to a version that resolves this vulnerability.

    Fixed in 7.2.7
  5. Upgrade

    Upgrade FortiOS to a version that resolves this vulnerability.

    Fixed in 8.0.0

Event History

Nov 18, 2025
Advisory Published
via FortiGuard·12:00 AM
Data Sourced
via FortiGuard·12:00 AM
DescriptionSeverityWeaknessAffected Software
CVE Published
via MITRE·05:01 PM
Data Sourced
via MITRE·05:01 PM
RemedyDescriptionSeverityWeakness
Data Sourced
via NVD·05:16 PM
DescriptionSeverityWeaknessAffected Software
Nov 21, 2025
Advisory Published
via FortiGuard·08:35 AM

Frequently Asked Questions

1

What is the severity of CVE-2025-53843?

CVE-2025-53843 is classified as a critical vulnerability due to its potential to allow unauthorized code execution.

2

How do I fix CVE-2025-53843?

To address CVE-2025-53843, upgrade to FortiOS version 7.6.4 or later, or 7.4.9 or later as applicable.

3

What affected versions are there for CVE-2025-53843?

CVE-2025-53843 affects FortiOS versions 7.0, 7.2, 7.4.0 through 7.4.8, and 7.6.0 through 7.6.3.

4

What is the nature of the vulnerability CVE-2025-53843?

CVE-2025-53843 is a stack-based buffer overflow that can be exploited via specially crafted packets.

5

Can CVE-2025-53843 lead to system compromise?

Yes, CVE-2025-53843 can allow an attacker to execute unauthorized commands, potentially compromising the system.

Company

Resources

Contact

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