How severe is CVE-2026-8620?

CVE-2026-8620 has a CVSS 3.x base score of 7.5, 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 low, and availability none.

Is CVE-2026-8620 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (20th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-8620?

CVE-2026-8620 primarily affects Ibm Websphere Application Server. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-8620?

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.

Does CVE-2026-8620 have an EU (EUVD) identifier?

Yes. CVE-2026-8620 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-31921.

When was CVE-2026-8620 published?

CVE-2026-8620 was published on 2026-05-26 and last updated on 2026-06-17.

CVE-2026-8620

CVE-2026-8620 is a high-severity vulnerability in Ibm Websphere Application Server with a CVSS 3.x base score of 7.5. 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-444.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 0% (20th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-31921
Weakness: CWE-444
Affected product: Ibm Websphere Application Server
Published: 2026-05-26
Last modified: 2026-06-17

Description

IBM Web Server Plug-ins for WebSphere Application Server and WebSphere Liberty 8.5, 9.0 IBM WebSphere Application Server and WebSphere Application Server Liberty are vulnerable to HTTP request smuggling in the Web Server Plug-ins through a specially crafted request.

Frequently asked questions

What is CVE-2026-8620?: IBM Web Server Plug-ins for WebSphere Application Server and WebSphere Liberty 8.5, 9.0 IBM WebSphere Application Server and WebSphere Application Server Liberty are vulnerable to HTTP request smuggling in the Web Server Plug-ins through a specially crafted request.
How severe is CVE-2026-8620?: CVE-2026-8620 has a CVSS 3.x base score of 7.5, 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 low, and availability none.
Is CVE-2026-8620 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (20th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-8620?: CVE-2026-8620 primarily affects Ibm Websphere Application Server. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-8620?: 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.
Does CVE-2026-8620 have an EU (EUVD) identifier?: Yes. CVE-2026-8620 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-31921.
When was CVE-2026-8620 published?: CVE-2026-8620 was published on 2026-05-26 and last updated on 2026-06-17.

References

https://www.ibm.com/support/pages/node/7274072

Affected products (2)

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

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