How severe is CVE-2026-86246?

CVE-2026-86246 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2026-86246 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (19th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-86246?

CVE-2026-86246 affects Apache Tomcat Native. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-86246?

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

When was CVE-2026-86246 published?

CVE-2026-86246 was published on 2026-09-23 and last updated on 2026-10-06.

CVE-2026-86246

CVE-2026-86246 is a critical-severity vulnerability in Apache Tomcat Native with a CVSS 3.x base score of 9.1. 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-1188.

Key facts

Severity: Critical (CVSS 3.x base score 9.1)
EPSS exploit prediction: 0% (19th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-1188
Affected product: Apache Tomcat Native
Published: 2026-09-23
Last modified: 2026-10-06

Description

Initialization of a resource with an insecure default vulnerability in Apache Tomcat Native enabled insecure options by default including ALLOW_CLIENT_RENEGOTIATION, NO_EXTENDED_MASTER_SECRET, IGNORE_UNEXPECTED_EOF and ALLOW_NO_DHE_KEX. This issue affects Apache Tomcat Native: from 2.0.0 through 2.0.15, from 1.3.0 through 1.3.8. Earlier unsupported versions may also be affected. Users are recommended to upgrade to version 2.0.16 or 1.3.9, which fix the issue.

Frequently asked questions

What is CVE-2026-86246?: Initialization of a resource with an insecure default vulnerability in Apache Tomcat Native enabled insecure options by default including ALLOW_CLIENT_RENEGOTIATION, NO_EXTENDED_MASTER_SECRET, IGNORE_UNEXPECTED_EOF and ALLOW_NO_DHE_KEX. This issue affects Apache Tomcat Native: from 2.0.0 through 2.0.15, from 1.3.0 through 1.3.8. Earlier unsupported versions may also be affected. Users are recommended to upgrade to version 2.0.16 or 1.3.9, which fix the issue.
How severe is CVE-2026-86246?: CVE-2026-86246 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2026-86246 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (19th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-86246?: CVE-2026-86246 affects Apache Tomcat Native. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-86246?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2026-86246 published?: CVE-2026-86246 was published on 2026-09-23 and last updated on 2026-10-06.

References

Affected products (1)

cpe:2.3:a:apache:tomcat_native:*:*:*:*:*:*:*:*

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