Security Digest · Vulnerability record

CVE-2026-68569: Apache Tomcat: Principal lookup can fail open in some cases

Improper Authentication vulnerability in Apache Tomcat meant that in some circumstances (e.g.

CVSS 8.1 High EPSS 0.5% · p39 Patch this week

Should you act?

Normal patch cycle

No exploitation signal; fix it in your next routine update if you are affected. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

  • No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
  • EPSS 0.5%, percentile 39: FIRST’s model estimates a 0.5% chance of exploitation activity in the next 30 days, higher than 39% of all scored CVEs (low). EPSS is a probability, not a verdict.
  • Needs an account (low (any account)). Exposure depends on who can log in.
  • Editorial verdict: Patch this week. Apache Tomcat August 2026: Security Constraint Bypasses — Upgrade Tomcat, including the copy embedded in Spring Boot apps, this week; the access-control bypasses matter wherever you rely on web.xml security constraints or container authentication, and none is known to be exploited.

What it is

Improper Authentication vulnerability in Apache Tomcat meant that in some circumstances (e.g. CLIENT-CERT, SPNEGO) that a user would be authenticated even if the user did not exist in the DataSourceRealm. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.24, from 10.1.0-M1 through 10.1.57, from 9.0.0.M1 through 9.0.120. The following versions were EOL at the time the CVE was created but are known to be affected: from 8.5.0 through 8.5.100, from 7.0.0 through 7.0.109. Other unsupported versions may also be affected. Users are recommended to upgrade to version 11.0.25, 10.1.58 or 9.0.121, which fix the issue.

Weakness type: CWE-287.

Product: Apache Software Foundation Apache Tomcat · Assigned by: apache · Published: 2026-08-25

Affected and fixed versions

VendorProductAffected versions (per CVE record)
Apache Software FoundationApache Tomcat11.0.0-M1 <= 11.0.24, 10.1.0-M1 <= 10.1.57, 9.0.0.M1 <= 9.0.120, 8.5.0 <= 8.5.100, 7.0.0 <= 7.0.109

Severity scores

Scored byCVSSScoreVector
CISA-ADP3.18.1 HighCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
  • Attack vector: network (remotely reachable)
  • Attack complexity: low
  • Privileges required: low (any account)
  • User interaction: none
  • Scope: unchanged

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

  • CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
  • CISA SSVC assessment: exploitation none, automatable no, technical impact total.
  • FIRST EPSS (model of 2026-10-21): 0.46% probability of exploitation activity in the next 30 days; percentile 39.

Timeline

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vendor and project advisories, patches

  1. lists.apache.org lists.apache.org

Vulnerability records

  1. CVE.org record CVE-2026-68569 cve.org
  2. NVD entry CVE-2026-68569 nvd.nist.gov

Other references from the CVE record and advisory

  1. openwall.com openwall.com

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