Cyber Resilience

CVE-2026-86246

Apache Tomcat Native 1.3.0 – 1.3.9

Published
23 September 2026
Modified
06 October 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 0.0028 19th percentile
Risk Priority 66 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2026-86246 is a critical-severity Initialization of a Resource with an Insecure Default (CWE-1188) vulnerability in Apache Tomcat Native. Its CVSS base score is 9.1 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Valid Accounts (T1078); ranked at the 19th 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 AC-6 (Least Privilege) and CM-2 (Baseline Configuration) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

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…

more

versions may also be affected. Users are recommended to upgrade to version 2.0.16 or 1.3.9, which fix the issue.

CWE(s)
CWE-1188

Related Threats

MITRE ATT&CK Enterprise Techniques

T1078 Valid Accounts Stealth
Adversaries may obtain and abuse credentials of existing accounts as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion.
attack.mitre.org →
T1078.001 Default Accounts Stealth
Adversaries may obtain and abuse credentials of a default account as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion.
attack.mitre.org →
T1133 External Remote Services Persistence
Adversaries may leverage external-facing remote services to initially access and/or persist within a network.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1542.002 Component Firmware Stealth
Adversaries may modify component firmware to persist on systems.
attack.mitre.org →
T1556 Modify Authentication Process Defense Impairment
Adversaries may modify authentication mechanisms and processes to access user credentials or enable otherwise unwarranted access to accounts.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-0387Shared CWE-1188
CVE-2025-41713Shared CWE-1188
CVE-2026-75926Shared CWE-1188
CVE-2025-31930Shared CWE-1188
CVE-2026-9039Shared CWE-1188
CVE-2025-31974Shared CWE-1188
CVE-2022-24706Shared CWE-1188
CVE-2025-35021Shared CWE-1188
CVE-2026-40994Shared CWE-1188
CVE-2025-41245Shared CWE-1188

Affected Assets

apache
tomcat native
1.3.0 — 1.3.9 · 2.0.0 — 2.0.16

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)
  • 11 hardening rules · 6 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V14.3.2
  • V6.3.2
  • V11.3.1
  • V13.2.3

Mitigating Controls (NIST 800-53 r5) AI

AC-6 Least Privilege partial match

Least privilege reduces the blast radius of any insecure default permissions that remain after initialization.

CM-2 Baseline Configuration partial match

Baseline configuration directly requires documenting and maintaining secure initial settings instead of insecure defaults.

CM-6 Configuration Settings partial match

Configuration settings mandate the most restrictive values be applied at initialization, eliminating reliance on insecure factory defaults.

SA-8 Security and Privacy Engineering Principles partial match

Security engineering principles include explicit requirements for secure defaults during resource initialization and design.

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.

ID.RA-09 partial match
prevents

Pre-acquisition integrity checks can reject products known to ship with insecure defaults.

PR.PS-01 partial match
prevents

Hardened baselines and configuration management directly replace insecure defaults with secure settings.

PR.PS-06 partial match
prevents

Secure development practices include designing products with secure defaults rather than insecure ones.

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.5.14 Information transfer partial match
removes
A.5.15 Access control partial match
removes
A.5.16 Identity management partial match
removes
A.5.17 Authentication information partial match
removes
A.5.18 Access rights partial match
removes
A.8.10 Information deletion partial match
removes

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (higher-evidence rows only; rows rated `none` are excluded).

Oracle Linux 8 (1 rule)
  • V-248823 OL 8 must not have the telnet-server package installed. prevents CWE-1188
RHEL 7 (1 rule)
  • V-204627 SNMP community strings on the Red Hat Enterprise Linux operating system must be changed from the default. prevents CWE-1188
Ubuntu 22.04 (1 rule)
  • V-260529 Ubuntu 22.04 LTS must be configured so that remote X connections are disabled, unless to fulfill documented and validated mission requirements. prevents CWE-1188
Ubuntu 24.04 (1 rule)
  • V-270708 Ubuntu 24.04 LTS must be configured so that remote X connections are disabled, unless to fulfill documented and validated mission requirements. prevents CWE-1188
Windows Server 2016 (1 rule)
  • V-224972 Active Directory Group Policy objects must have proper access control permissions. prevents CWE-1188
Windows Server 2019 (1 rule)
  • V-205741 Windows Server 2019 Active Directory Group Policy objects must have proper access control permissions. prevents CWE-1188

References