8.2
HIGH CVSS 4.0
CVE-2026-56091
Apache Shiro: Authentication bypass in Guice-Web integration
Description

When using Apache Shiro with the shiro-guice module in a web servlet context, a specially crafted HTTP request may cause an authentication bypass. This vulnerability is similar to https://www.cve.org/CVERecord?id=CVE-2020-1957 https://www.cve.org/CVERecord , except that it affects the `shiro-guice` module instead of the `shiro-spring` module. This issue affects all Apache Shiro versions through 2.x, and 3.0.0-alpha-1 only when using `shiro-guice` module in a web servlet context. Upgrade to version 3.0.0 or later, which fixes the issue.

INFO

Published Date :

June 25, 2026, 9:16 a.m.

Last Modified :

June 25, 2026, 1:27 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-56091 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Apache shiro
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 4.0 HIGH f0158376-9dc2-43b6-827c-5f631a4d8d09
CVSS 4.0 HIGH [email protected]
Solution
Upgrade Apache Shiro to a version that includes the fix for the authentication bypass vulnerability.
  • Upgrade Apache Shiro to version 3.0.0 or later.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-56091.

URL Resource
https://lists.apache.org/thread/onmtxmy2qonbpx7xlw3o34x8sctv47r7
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-56091 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-56091 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-56091 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-56091 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Jun. 25, 2026

    Action Type Old Value New Value
    Added SSVC {'id': 'CVE-2026-56091', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-06-25T12:10:08.791843Z'}
  • New CVE Received by [email protected]

    Jun. 25, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'Apache Software Foundation', 'product': 'Apache Shiro', 'versions': [{'status': 'affected', 'version': '0', 'versionType': 'semver', 'lessThanOrEqual': '2.99.99'}, {'status': 'affected', 'version': '3.0.0-alpha-0', 'versionType': 'semver', 'lessThanOrEqual': '3.0.0-alpha-1'}], 'packageName': 'org.apache.shiro:shiro-guice', 'collectionURL': 'https://repo.maven.apache.org/maven2', 'defaultStatus': 'unaffected'}]
    Added Description When using Apache Shiro with the shiro-guice module in a web servlet context, a specially crafted HTTP request may cause an authentication bypass. This vulnerability is similar to https://www.cve.org/CVERecord?id=CVE-2020-1957 https://www.cve.org/CVERecord , except that it affects the `shiro-guice` module instead of the `shiro-spring` module. This issue affects all Apache Shiro versions through 2.x, and 3.0.0-alpha-1 only when using `shiro-guice` module in a web servlet context. Upgrade to version 3.0.0 or later, which fixes the issue.
    Added CVSS V4.0 AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:P/AU:Y/R:X/V:D/RE:L/U:Amber
    Added CWE CWE-289
    Added Reference https://lists.apache.org/thread/onmtxmy2qonbpx7xlw3o34x8sctv47r7
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.