How severe is CVE-2026-55956?

CVE-2026-55956 has a CVSS 3.x base score of 6.5, rated medium 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 none.

Is CVE-2026-55956 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (33rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-55956?

CVE-2026-55956 affects Apache Tomcat. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-55956?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2026-55956 published?

CVE-2026-55956 was published on 2026-06-29 and last updated on 2026-07-02.

CVE-2026-55956

CVE-2026-55956 is a medium-severity vulnerability in Apache Tomcat with a CVSS 3.x base score of 6.5. 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-285.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 0% (33rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-285
Affected product: Apache Tomcat
Published: 2026-06-29
Last modified: 2026-07-02

Description

Improper Authorization vulnerability in Apache Tomcat leads to security constraints specified for the default servlet ignoring any method or method omission configured as part of the constraint. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.22, from 10.1.0-M1 through 10.1.55, from 9.0.0.M1 through 9.0.118, from 8.5.0 through 8.5.100, from 7.0.0 through 7.0.109. Other versions that have reached end of support may also be affected. Users are recommended to upgrade to version 11.0.23, 10.1.56 or 9.0.119, which fix the issue.

Frequently asked questions

What is CVE-2026-55956?: Improper Authorization vulnerability in Apache Tomcat leads to security constraints specified for the default servlet ignoring any method or method omission configured as part of the constraint. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.22, from 10.1.0-M1 through 10.1.55, from 9.0.0.M1 through 9.0.118, from 8.5.0 through 8.5.100, from 7.0.0 through 7.0.109. Other versions that have reached end of support may also be affected. Users are recommended to upgrade to version 11.0.23, 10.1.56 or 9.0.119, which fix the issue.
How severe is CVE-2026-55956?: CVE-2026-55956 has a CVSS 3.x base score of 6.5, rated medium 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 none.
Is CVE-2026-55956 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (33rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-55956?: CVE-2026-55956 affects Apache Tomcat. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-55956?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2026-55956 published?: CVE-2026-55956 was published on 2026-06-29 and last updated on 2026-07-02.

References

Affected products (1)

cpe:2.3:a:apache:tomcat:*:*:*:*:*:*:*:*

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