Cyber Resilience

CVE-2026-55276

Apache Tomcat ≤ 9.0.119

Published
29 June 2026
Modified
02 July 2026
Patch / advisory
View advisory
CVSS Score v3.1 9.1
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
EPSS Score 0.0054 43th percentile
Risk Priority 67 floored blend · peak EPSS

Summary

CVE-2026-55276 is a critical-severity Always-Incorrect Control Flow Implementation (CWE-670) vulnerability in Apache Tomcat. Its CVSS base score is 9.1 (Critical).

Operationally, ranked at the 43th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SA-15 (Development Process, Standards, and Tools) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

Always-Incorrect Control Flow Implementation vulnerability in Apache Tomcat meant that special roles and empty authorisation constraints were not included when the effective web.xml was logged. 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…

more

through 9.0.118, from 8.5.0 through 8.5.100. 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 fixes the issue.

CWE(s)
CWE-670

Related Threats

CVEs Like This One

CVE-2026-53404Same product: Apache Tomcat
CVE-2026-66299Same product: Apache Tomcat
CVE-2026-25854Same product: Apache Tomcat
CVE-2024-21733Same product: Apache Tomcat
CVE-2026-55955Same product: Apache Tomcat
CVE-2025-49125Same product: Apache Tomcat
CVE-2026-55956Same product: Apache Tomcat
CVE-2026-34500Same product: Apache Tomcat
CVE-2025-52434Same product: Apache Tomcat
CVE-2025-66614Same product: Apache Tomcat

Affected Assets

apache
tomcat
≤ 9.0.119 · 10.1.0 — 10.1.56 · 11.0.0 — 11.0.23

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V9.2.1

Mitigating Controls (NIST 800-53 r5) AI

SA-11 Developer Testing and Evaluation good match

Developer testing and evaluation at post-design stages directly exercises control-flow paths and reveals mismatches between implemented and intended behavior.

SA-15 Development Process, Standards, and Tools partial match

Requiring a documented development process and supporting tools reduces the chance that incorrect control-flow logic is introduced in the first place.

SI-2 Flaw Remediation partial match

Flaw identification and remediation processes can locate and correct control-flow errors once they manifest as incorrect runtime behavior.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly prevent incorrect control-flow implementations via reviews, testing, and static analysis.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing in development and acceptance can detect paths that deviate from intended logic.

A.8.25 Secure development life cycle partial match
prevents

Secure development lifecycle processes can catch incorrect control-flow logic during design and code review.

A.8.28 Secure coding partial match
prevents

Secure coding standards and reviews directly target flawed control-flow implementations.

A.8.32 Change management partial match
prevents

Change-management gates may prevent deployment of flawed logic but do not address the coding defect itself.

References