CyberSecBulletin
CVE-2026-59084NVD status: Analyzed

Apache Tomcat: Insufficient Technical Documentation

CVE-2026-59084 is a critical-severity insufficient technical documentation vulnerability in Apache Tomcat from Apache, with a CVSS 3.1 base score of 9.1 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected Apache Tomcat versions: 11.0.0-M1 through 11.0.23; 10.1.0-M1 through 10.1.56; 9.0.13 through 9.0.119, and others listed below. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.51% chance of exploitation within 30 days, which is low compared with other CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Check which version of Apache Tomcat you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on lists.apache.org for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
ApacheApache Tomcat11.0.0-M1 through 11.0.23; 10.1.0-M1 through 10.1.56; 9.0.13 through 9.0.119; 8.5.38 through 8.5.100; 7.0.100 through 7.0.109Not stated
ApacheTomcat7.0.100 through 7.0.109; 8.5.38 through 8.5.100; 9.0.13 through 9.0.119; 10.1.0 through 10.1.56; 11.0.0 through 11.0.23Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
NoneAvailability is not affected.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N. Scored by CISA (ADP).

Official description

Insufficient Technical Documentation vulnerability in Apache Tomcat since the requirements to securely configure the EncryptInterceptor were not clearly documented. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.23, from 10.1.0-M1 through 10.1.56, from 9.0.13 through 9.0.119, from 8.5.38 through 8.5.100, from 7.0.100 through 7.0.109. Other versions that have reached end of support may also be affected. Users are recommended to upgrade to version 11.0.24, 10.1.57 or 9.0.120 which fix the issue.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Insufficient Technical Documentation

The product does not contain sufficient technical or engineering documentation (whether on paper or in electronic form) that contains descriptions of all of the relevant software/hardware elements of the product.

How developers prevent this class of flaw

  • Ensure that design documentation is detailed enough to allow for post-manufacturing verification.

More Insufficient Technical Documentation vulnerabilities (CWE-1059)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Other vulnerabilities in Apache Tomcat

All Apache Tomcat vulnerabilities

Recent Insufficient Technical Documentation vulnerabilities

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