How severe is CVE-2026-8400?

CVE-2026-8400 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-8400 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (40th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-8400?

CVE-2026-8400 primarily affects Ibm Websphere Application Server. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-8400?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2026-8400 published?

CVE-2026-8400 was published on 2026-08-05 and last updated on 2026-08-10.

CVE-2026-8400

CVE-2026-8400 is a high-severity vulnerability in Ibm Websphere Application Server with a CVSS 3.x base score of 8.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-470.

Key facts

Severity: High (CVSS 3.x base score 8.1)
EPSS exploit prediction: 0% (40th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-470
Affected product: Ibm Websphere Application Server
Published: 2026-08-05
Last modified: 2026-08-10

Description

IBM WebSphere Application Server 8.5, and 9.0 and IBM WebSphere Application Server - Liberty Continuous delivery has a flaw in the ORB component in IBM SDK, Java Technology Edition, may allow a malicious IIOP server to induce loading and instantation of arbitrary classes.

Frequently asked questions

What is CVE-2026-8400?: IBM WebSphere Application Server 8.5, and 9.0 and IBM WebSphere Application Server - Liberty Continuous delivery has a flaw in the ORB component in IBM SDK, Java Technology Edition, may allow a malicious IIOP server to induce loading and instantation of arbitrary classes.
How severe is CVE-2026-8400?: CVE-2026-8400 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-8400 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (40th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-8400?: CVE-2026-8400 primarily affects Ibm Websphere Application Server. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-8400?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2026-8400 published?: CVE-2026-8400 was published on 2026-08-05 and last updated on 2026-08-10.

References

https://www.ibm.com/support/pages/node/7282446

Affected products (3)

cpe:2.3:a:ibm:websphere_application_server:-:*:*:*:liberty:*:*:*
cpe:2.3:a:ibm:websphere_application_server:8.5.0.0:*:*:*:-:*:*:*
cpe:2.3:a:ibm:websphere_application_server:9.0.0.0:*:*:*:-:*:*:*

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