CVE-2026-87676

Management-daemon crash via oversized certificate AKI

Published Oct 8, 2026 · Updated Oct 8, 2026

Stack-based buffer overflow in Brocade Fabric OS before 10.0.1 allows remote authenticated users to crash the management daemon. The security library fails to validate the length of an X.509 PEM certificate's Authority Key Identifier extension before copying parsed tokens into a stack buffer. Exploitation requires administrative permission to import a custom certificate and processing or display of its attributes; the reported consequence is a management-daemon crash, not code execution.

CVSS severity6.9
Medium
EPSS probability0.12%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stack-based buffer overflow in Brocade Fabric OS before 10.0.1 allows remote authenticated users to crash the management daemon. The security library fails to validate the length of an X.509 PEM certificate's Authority Key Identifier extension before copying parsed tokens into a stack buffer. Exploitation requires administrative permission to import a custom certificate and processing or display of its attributes; the reported consequence is a management-daemon crash, not code execution.

The record

CVE
CVE-2026-87676
Published
Oct 8, 2026
Updated
Oct 8, 2026
Vendor
Brocade Communications Systems
Product
Fabric OS
Classifications
CWE-121, T1499.004
Attack vector
adjacent
Privileges
admin

Timeline

How it unfolded

  1. Oct 8, 2026CVE publishedPublication date reported by the CVE source.
  2. Oct 8, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <10.0.1

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesadmin

What is affected?

Brocade Communications Systems · Fabric OSversion=0 <10.0.1

Published CVSS scores

6.9BroadcomCVSS:4.0/AV:A/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectoradjacent
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-121Stack-based Buffer Overflow
T1499.004Endpoint Denial of Service: Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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