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CVE-2026-23903· NVD / CVE Program· CNA apache

Apache Shiro: Auth bypass when accessing static files only on case-insensitive filesystems

Noroxi assessment

Priority: Monitor (action score 21/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.40% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • According to CISA the attack is automatable: targets can be found by mass scanning.
  • Fixed version: Apache Software Foundation Apache Shiro 2.0.7.

Low priority for now. Upgrade to Apache Software Foundation Apache Shiro 2.0.7 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

Authentication Bypass by Alternate Name vulnerability in Apache Shiro. This issue affects Apache Shiro: before 2.0.7. Users are recommended to upgrade to version 2.0.7, which fixes the issue. The issue only effects static files. If static files are served from a case-insensitive filesystem, such as default macOS setup, static files may be accessed by varying the case of the filename in the request. If only lower-case (common default) filters are present in Shiro, they may be bypassed this way. Shiro 2.1.0 and later has a new parameters to remediate this issue shiro.ini: filterChainResolver.caseInsensitive = true application.properties: shiro.caseInsensitive=true Shiro 3.0.0 and later makes this the default in shiro.ini-based configurations. Shiro 3.0.1 and later makes this the default in all configurations, including programmatic and Spring / Spring Boot.

MediumCVSS 5.3 · v3.1—No exploit Fix available
Published
Feb 9, 2026
Updated
Aug 20, 2026
EPSS
0.4% · 32th percentile

Report tools

JSON

Action score

21

Monitor

Low priority for now.

CVSS
21 / 40 · 5.3 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.4%

CISA SSVC decision

Exploitation
none
Automatable
yes
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2026-23903

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
apacheshiro

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • apache shirobefore 2.0.7

Versions reported by the vendor

Affected version ranges reported by the assigning authority (apache). Independent of NVD's CPE analysis and usually ahead of it.

  • Apache Software Foundation Apache Shiro

    • before 2.0.7affected · semver

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:12shiroall versions—
Mavenorg.apache.shiro:shiro-springbefore 2.1.02.1.0

Other highest-scoring records for the same primary product.

  • CVE-2020-17523Apache Shiro before 1.7.1, when using Apache Shiro with Spring, a specially crafted HTTP request may cause an authentication bypass.
    65This week
  • CVE-2021-41303Apache Shiro before 1.8.0, when using Apache Shiro with Spring Boot, a specially crafted HTTP request may cause an authentication bypass
    62This week
  • CVE-2022-32532Authentication Bypass Vulnerability
    47Plan
  • CVE-2020-11989Apache Shiro before 1.5.3, when using Apache Shiro with Spring dynamic controllers, a specially crafted request may cause an authentication
    46Plan
  • CVE-2020-1957Apache Shiro before 1.5.2, when using Apache Shiro with Spring dynamic controllers, a specially crafted request may cause an authentication
    46Plan
  • CVE-2020-13933Apache Shiro before 1.6.0, when using Apache Shiro, a specially crafted HTTP request may cause an authentication bypass.
    43Plan

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
Apache Software Foundation Apache Shiro2.0.7Vendor (CNA)
Maven:org.apache.shiro:shiro-spring2.1.0Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

—

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

  • CVE-2026-44598105 days apartApache Shiro Jakarta EE module: Open redirect and SSRF (requires valid credentials)
    20Monitor

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
low · data can be read
Integrity
none
Availability
none
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
Low
Integrity impact
None
Availability impact
None

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

nvd-secondary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. Fix✗ → ✓

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References

Show all references (1 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records