Is CVE-2026-8858 in the CISA KEV catalog?

No. CVE-2026-8858 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2026-8858?

CVE-2026-8858 has a CVSS v3 base score of 7.5 (HIGH).

What is the EPSS score for CVE-2026-8858?

CVE-2026-8858 has an EPSS score of 0.25% (16th percentile), estimating the probability of exploitation in the next 30 days.

CVE & CISA-KEV Catalog

CVE-2026-8858

HIGH

7.5

CVSS v3

NVD

Description

IBM i 7.6, 7.5, 7.4, and 7.3, IBM WebSphere Application Server and IBM WebSphere Application Server Liberty are vulnerable to remote code execution and denial of service in the WebSphere Web Server Plug-in component. This vulnerability can be exploited when an attacker impersonates the application server and sends crafted responses to the plug-in.

CWE-94Code Injection

CVSS v3 Vector

Exploitability

Attack VectorAdjacent

Attack ComplexityHigh

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

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

Exploit Intelligence

0.25%probability of exploitation in 30 days

16thpercentile

Low risk: more likely to be exploited than 16% of all known CVEs.

References

https://www.ibm.com/support/pages/node/7277344

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-06-23.