---
title: "CVE-2026-65905: Apache Tomcat's DIGEST authenticator has an Authentication Bypass by Capture-replay vulnerability"
url: https://erroneo.us/security/cve/CVE-2026-65905/
description: "CVE-2026-65905 (org.apache.tomcat:tomcat (Maven)): Authentication Bypass by Capture-replay vulnerability in Apache Tomcat's DIGEST authenticator. If, before…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-08-25
date_modified: 2026-10-21
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-65905"
kev: false
cvss: 9.8
epss: 0.00562
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-65905: Apache Tomcat's DIGEST authenticator has an Authentication Bypass by Capture-replay vulnerability

**Signal:** Critical and remotely reachable. No known exploitation yet, but it is network-reachable without credentials. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- 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 0.6% , percentile 46: FIRST’s model estimates a 0.6% chance of exploitation activity in the next 30 days, higher than 46% 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

Authentication Bypass by Capture-replay vulnerability in Apache Tomcat's DIGEST authenticator. If, before windowSize requests have been made, a client makes a DIGEST authenticated request with a nonceCount on the upper boundary of the replay window then that request is replayable once only while the associated nonceCount remains within the replay window. 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 7.0.30 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.

## Affected packages

- Maven `org.apache.tomcat:tomcat` >= 11.0.0-M1, < 11.0.25 → fixed: 11.0.25
- Maven `org.apache.tomcat:tomcat` >= 10.1.0-M1, < 10.1.58 → fixed: 10.1.58
- Maven `org.apache.tomcat:tomcat` >= 9.0.0.M1, < 9.0.121 → fixed: 9.0.121
- Maven `org.apache.tomcat:tomcat` >= 8.5.0, <= 8.5.100 → fixed: none listed
- Maven `org.apache.tomcat:tomcat` >= 7.0.30, <= 7.0.109 → fixed: none listed
- Maven `org.apache.tomcat.embed:tomcat-embed-core` >= 11.0.0-M1, < 11.0.25 → fixed: 11.0.25
- Maven `org.apache.tomcat.embed:tomcat-embed-core` >= 10.1.0-M1, < 10.1.58 → fixed: 10.1.58
- Maven `org.apache.tomcat.embed:tomcat-embed-core` >= 9.0.0.M1, < 9.0.121 → fixed: 9.0.121
- Maven `org.apache.tomcat.embed:tomcat-embed-core` >= 8.5.0, <= 8.5.100 → fixed: none listed
- Maven `org.apache.tomcat.embed:tomcat-embed-core` >= 7.0.30, <= 7.0.109 → fixed: none listed
- Maven `org.apache.tomcat:tomcat-catalina` >= 11.0.0-M1, < 11.0.25 → fixed: 11.0.25
- Maven `org.apache.tomcat:tomcat-catalina` >= 10.1.0-M1, < 10.1.58 → fixed: 10.1.58
- Maven `org.apache.tomcat:tomcat-catalina` >= 9.0.0.M1, < 9.0.121 → fixed: 9.0.121
- Maven `org.apache.tomcat:tomcat-catalina` >= 8.5.0, <= 8.5.100 → fixed: none listed
- Maven `org.apache.tomcat:tomcat-catalina` >= 7.0.30, <= 7.0.109 → fixed: none listed

## Affected products (CVE record)

- Apache Software Foundation Apache Tomcat: 11.0.0-M1 <= 11.0.24, 10.1.0-M1 <= 10.1.57, 9.0.0.M1 <= 9.0.120, 8.5.0 <= 8.5.100, 7.0.30 <= 7.0.109

## Severity

- CISA-ADP CVSS 3.1: 9.8 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`
- GitHub CVSS 3.1: 9.8 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`

## Exploitation

- 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): 0.56% probability of exploitation activity in the next 30 days; percentile 46.

## Sources

- [lists.apache.org](https://lists.apache.org/thread/9v114xlpgbzrrbzz5vf9f6r2q4wnxwwj)
- [GitHub Advisory GHSA-9xv2-5v5q-p794](https://github.com/advisories/GHSA-9xv2-5v5q-p794)
- [CVE.org record CVE-2026-65905](https://www.cve.org/CVERecord?id=CVE-2026-65905)
- [NVD entry CVE-2026-65905](https://nvd.nist.gov/vuln/detail/CVE-2026-65905)
- [openwall.com](http://www.openwall.com/lists/oss-security/2026/08/26/4)

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Source page: https://erroneo.us/security/cve/CVE-2026-65905/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt