erroneo.us
Search all guides⌘K

Security Digest · Vulnerability record

CVE-2026-65182: Apache Tomcat has an Improper Access Control, Incorrect Authorization vulnerability

Improper Access Control, Incorrect Authorization vulnerability in Apache Tomcat leads to security constraint bypass if a constraint for a longer path is specified before a more restrictive constraint for a shorter sub-path.

CVSS 9.1 Critical EPSS 0.5% · p44 Patch this week

Updated By erroneo.us Security Desk11 references Seen in the digest for Aug 25, 2026

Should you act?

Critical and remotely reachable

No known exploitation yet, but it is network-reachable without credentials. 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 44: FIRST’s model estimates a 0.5% chance of exploitation activity in the next 30 days, higher than 44% of all scored CVEs (low). EPSS is a probability, not a verdict.
  • Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
  • Only applies if your dependency tree includes org.apache.tomcat:tomcat (Maven) >= 11.0.0-M1, < 11.0.25, fixed in 11.0.25; org.apache.tomcat:tomcat (Maven) >= 10.1.0-M1, < 10.1.58, fixed in 10.1.58; org.apache.tomcat:tomcat (Maven) >= 9.0.0-M1, < 9.0.121, fixed in 9.0.121; org.apache.tomcat:tomcat (Maven) >= 8.5.0, <= 8.5.100, no fixed version listed. Check your lockfile, including transitive dependencies.
  • 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 Access Control, Incorrect Authorization vulnerability in Apache Tomcat leads to security constraint bypass if a constraint for a longer path is specified before a more restrictive constraint for a shorter sub-path. 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, from 8.5.0 through 8.5.100, from 7.0.0 through 7.0.109. Users are recommended to upgrade to version 11.0.25, 10.1.58, 9.0.121, which fixes the issue.

From the GitHub advisory

Improper Access Control, Incorrect Authorization vulnerability in Apache Tomcat leads to security constraint bypass if a constraint for a longer path is specified before a more restrictive constraint for a shorter sub-path.

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, from 8.5.0 through 8.5.100, from 7.0.0 through 7.0.109.

Users are recommended to upgrade to version 11.0.25, 10.1.58, 9.0.121, which fixes the issue.

Weakness type: CWE-284, CWE-863.

Product: org.apache.tomcat:tomcat (Maven) · Assigned by: apache · Published: 2026-08-25

Affected and fixed versions

EcosystemPackageVulnerableFirst fixed
Mavenorg.apache.tomcat:tomcat>= 11.0.0-M1, < 11.0.2511.0.25
Mavenorg.apache.tomcat:tomcat>= 10.1.0-M1, < 10.1.5810.1.58
Mavenorg.apache.tomcat:tomcat>= 9.0.0-M1, < 9.0.1219.0.121
Mavenorg.apache.tomcat:tomcat>= 8.5.0, <= 8.5.100none listed
Mavenorg.apache.tomcat:tomcat>= 7.0.0, <= 7.0.109none listed
Mavenorg.apache.tomcat:tomcat-catalina>= 11.0.0-M1, < 11.0.2511.0.25
Mavenorg.apache.tomcat:tomcat-catalina>= 10.1.0-M1, < 10.1.5810.1.58
Mavenorg.apache.tomcat:tomcat-catalina>= 9.0.0-M1, < 9.0.1219.0.121
Mavenorg.apache.tomcat:tomcat-catalina>= 8.5.0, <= 8.5.100none listed
Mavenorg.apache.tomcat:tomcat-catalina>= 7.0.0, <= 7.0.109none listed
Mavenorg.apache.tomcat.embed:tomcat-embed-core>= 11.0.0-M1, < 11.0.2511.0.25
Mavenorg.apache.tomcat.embed:tomcat-embed-core>= 10.1.0-M1, < 10.1.5810.1.58
Mavenorg.apache.tomcat.embed:tomcat-embed-core>= 9.0.0-M1, < 9.0.1219.0.121
Mavenorg.apache.tomcat.embed:tomcat-embed-core>= 8.5.0, <= 8.5.100none listed
Mavenorg.apache.tomcat.embed:tomcat-embed-core>= 7.0.0, <= 7.0.109none listed
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-ADP3.19.1 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
GitHub3.19.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
  • Attack vector: network (remotely reachable)
  • Attack complexity: low
  • Privileges required: none (no login)
  • 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 yes, technical impact total.
  • FIRST EPSS (model of 2026-10-21): 0.54% probability of exploitation activity in the next 30 days; percentile 44.

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. GitHub Advisory GHSA-gcx9-497g-6cp6 github.com
  2. CVE.org record CVE-2026-65182 cve.org
  3. NVD entry CVE-2026-65182 nvd.nist.gov

Other references from the CVE record and advisory

  1. openwall.com openwall.com
  2. github.com github.com
  3. github.com github.com
  4. github.com github.com
  5. tomcat.apache.org tomcat.apache.org
  6. tomcat.apache.org tomcat.apache.org
  7. tomcat.apache.org tomcat.apache.org

Critical Maven advisories · Today’s Security Digest