How severe is CVE-2026-23904?

CVE-2026-23904 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2026-23904 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-23904?

CVE-2026-23904 affects Apache Kyuubi. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-23904?

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-2026-23904 published?

CVE-2026-23904 was published on 2026-07-29 and last updated on 2026-08-05.

CVE-2026-23904

CVE-2026-23904 is a high-severity vulnerability in Apache Kyuubi with a CVSS 3.x base score of 7.3. 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-923.

Key facts

Severity: High (CVSS 3.x base score 7.3)
EPSS exploit prediction: 1% (49th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-923
Affected product: Apache Kyuubi
Published: 2026-07-29
Last modified: 2026-08-05

Description

Kyuubi Engine UI proxy accepts a host and port from the request path and proxies HTTP requests to that destination. A remote requester with network access to the proxy can cause the Kyuubi server to send HTTP requests to arbitrary reachable hosts, resulting in SSRF or open-proxy behavior. This issue affects Apache Kyuubi: from 1.8.0 before 1.12.0. Users are recommended to upgrade to version 1.12.0, which disables the proxy by default. To restore proxied Engine UI, set kyuubi.frontend.rest.engine.ui.proxy.enabled=true and configure allowed target hosts with kyuubi.frontend.rest.engine.ui.proxy.hosts.

Frequently asked questions

What is CVE-2026-23904?: Kyuubi Engine UI proxy accepts a host and port from the request path and proxies HTTP requests to that destination. A remote requester with network access to the proxy can cause the Kyuubi server to send HTTP requests to arbitrary reachable hosts, resulting in SSRF or open-proxy behavior. This issue affects Apache Kyuubi: from 1.8.0 before 1.12.0. Users are recommended to upgrade to version 1.12.0, which disables the proxy by default. To restore proxied Engine UI, set kyuubi.frontend.rest.engine.ui.proxy.enabled=true and configure allowed target hosts with kyuubi.frontend.rest.engine.ui.proxy.hosts.
How severe is CVE-2026-23904?: CVE-2026-23904 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2026-23904 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-23904?: CVE-2026-23904 affects Apache Kyuubi. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-23904?: 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-2026-23904 published?: CVE-2026-23904 was published on 2026-07-29 and last updated on 2026-08-05.

References

Affected products (1)

cpe:2.3:a:apache:kyuubi:*:*:*:*:*:*:*:*

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