Vulnerability-Lookup

GHSA-C244-P6M5-VQJ6

Vulnerability from github – Published: 2026-02-09 12:30 – Updated: 2026-02-11 19:48

Summary

Apache Shiro has an Authentication Bypass

Details

Impact

Authentication Bypass: A vulnerability exists in Apache Shiro that allows authentication bypass for static files when served from a case-insensitive filesystem (such as the default configuration on macOS or Windows).

The issue arises when Shiro's URL filters are configured with lower-case rules (a common default), but the underlying operating system treats mixed-case filenames as identical. An attacker can access protected static resources by varying the capitalization of the filename in the request (e.g., requesting /SECRET.TXT to bypass a rule for /secret.txt).

This issue specifically affects static file handling and does not impact dynamic resource paths that are case-sensitive.

Patches

Users should upgrade to Apache Shiro 2.1.0 or later.

Important Configuration Note: Version 2.1.0 introduces a new configuration parameter to handle case-insensitivity, which must be enabled manually to resolve the issue:

shiro.ini: ini filterChainResolver.caseInsensitive = true
Spring Boot (application.properties): properties shiro.caseInsensitive=true

Note: Apache Shiro 3.0.0 (upcoming) will enable this setting by default.

Workarounds

Ensure that the filesystem hosting the application is case-sensitive (e.g., Linux/Unix).
Manually configure all Shiro filter chains to handle all possible case variations of protected filenames (not recommended due to complexity).

Resources

Severity

5.3 (Medium)


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

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 2.0.6"
      },
      "package": {
        "ecosystem": "Maven",
        "name": "org.apache.shiro:shiro-spring"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.1.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-23903"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-289"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-02-11T19:48:43Z",
    "nvd_published_at": "2026-02-09T10:15:57Z",
    "severity": "MODERATE"
  },
  "details": "### Impact\n\n**Authentication Bypass:**\nA vulnerability exists in Apache Shiro that allows authentication bypass for static files when served from a case-insensitive filesystem (such as the default configuration on macOS or Windows).\n\nThe issue arises when Shiro\u0027s URL filters are configured with lower-case rules (a common default), but the underlying operating system treats mixed-case filenames as identical. An attacker can access protected static resources by varying the capitalization of the filename in the request (e.g., requesting `/SECRET.TXT` to bypass a rule for `/secret.txt`).\n\nThis issue specifically affects static file handling and does not impact dynamic resource paths that are case-sensitive.\n\n### Patches\nUsers should upgrade to Apache Shiro **2.1.0** or later.\n\n**Important Configuration Note:**\nVersion 2.1.0 introduces a new configuration parameter to handle case-insensitivity, which must be enabled manually to resolve the issue:\n\n* **shiro.ini:**\n    ```ini\n    filterChainResolver.caseInsensitive = true\n    ```\n* **Spring Boot (application.properties):**\n    ```properties\n    shiro.caseInsensitive=true\n    ```\n\n*Note: Apache Shiro 3.0.0 (upcoming) will enable this setting by default.*\n\n### Workarounds\n* Ensure that the filesystem hosting the application is case-sensitive (e.g., Linux/Unix).\n* Manually configure all Shiro filter chains to handle all possible case variations of protected filenames (not recommended due to complexity).\n\n### Resources\n* [CVE-2026-23903](https://nvd.nist.gov/vuln/detail/CVE-2026-23903)\n* [Mailing List Announcement](https://lists.apache.org/thread/5jjf0hnjcol58z2m5y255c7scz1lnp8k)\n* [OSS-Security List](http://www.openwall.com/lists/oss-security/2026/02/08/1)",
  "id": "GHSA-c244-p6m5-vqj6",
  "modified": "2026-02-11T19:48:43Z",
  "published": "2026-02-09T12:30:22Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-23903"
    },
    {
      "type": "WEB",
      "url": "https://github.com/apache/shiro/commit/3b9638b957495004599aeaf24ba8949e309f26e8"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/apache/shiro"
    },
    {
      "type": "WEB",
      "url": "https://lists.apache.org/thread/5jjf0hnjcol58z2m5y255c7scz1lnp8k"
    },
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2026/02/08/1"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Apache Shiro has an Authentication Bypass"
}

CVE-2026-23903 (GCVE-0-2026-23903)

Vulnerability from cvelistv5 – Published: 2026-02-09 09:26 – Updated: 2026-08-20 09:44

Title

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

Summary

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.

Severity

5.3 (Medium)


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

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-02-09 16:17 UTC

CWE

CWE-289 - Authentication Bypass by Alternate Name

Assigner

apache mitre root

References

2 references

URL	Tags
https://lists.apache.org/thread/5jjf0hnjcol58z2m5…	vendor-advisory
http://www.openwall.com/lists/oss-security/2026/02/08/1

Impacted products

1 product

Vendor	Product	Version
Apache Software Foundation	Apache Shiro	Affected: 0 , < 2.0.7 (semver)

Credits

Jesse Yang Lenny Pimak

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2026-02-09T10:25:43.212Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "url": "http://www.openwall.com/lists/oss-security/2026/02/08/1"
          }
        ],
        "title": "CVE Program Container"
      },
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "NETWORK",
              "availabilityImpact": "NONE",
              "baseScore": 5.3,
              "baseSeverity": "MEDIUM",
              "confidentialityImpact": "LOW",
              "integrityImpact": "NONE",
              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2026-23903",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-02-09T16:17:20.608697Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-02-09T16:17:43.204Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://repo.maven.apache.org/maven2",
          "defaultStatus": "unaffected",
          "packageName": "org.apache.shiro:shiro-web",
          "product": "Apache Shiro",
          "vendor": "Apache Software Foundation",
          "versions": [
            {
              "lessThan": "2.0.7",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Jesse Yang"
        },
        {
          "lang": "en",
          "type": "remediation developer",
          "value": "Lenny Pimak"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "\u003cp\u003eAuthentication Bypass by Alternate Name vulnerability in Apache Shiro.\u003c/p\u003e\u003cp\u003eThis issue affects Apache Shiro: before 2.0.7.\u003c/p\u003e\u003cp\u003eUsers are recommended to upgrade to version 2.0.7, which fixes the issue.\u003c/p\u003eThe issue only effects static files. If static files are served from a case-insensitive filesystem,\u003cbr\u003esuch as default macOS setup, static files may be accessed by varying the case of the filename in the request.\u003cbr\u003eIf only lower-case (common default) filters are present in Shiro, they may be bypassed this way.\u003cbr\u003e\u003cbr\u003eShiro 2.1.0 and later has a new parameters to remediate this issue\u003cbr\u003eshiro.ini: \u003cspan style=\"background-color: rgba(129, 139, 152, 0.12);\"\u003efilterChainResolver.caseInsensitive = true\u003cbr\u003e\u003c/span\u003eapplication.properties: shiro\u003cspan style=\"background-color: rgba(129, 139, 152, 0.12);\"\u003e.caseInsensitive=true\u003cbr\u003e\u003c/span\u003e\u003cbr\u003eShiro 3.0.0 and later makes this the default in\u0026nbsp;\u003ctt\u003eshiro.ini\u003c/tt\u003e-based configurations.\u003cbr\u003eShiro 3.0.1 and later makes this the default in all configurations, including programmatic and Spring / Spring Boot."
            }
          ],
          "value": "Authentication Bypass by Alternate Name vulnerability in Apache Shiro.\n\nThis issue affects Apache Shiro: before 2.0.7.\n\nUsers are recommended to upgrade to version 2.0.7, which fixes the issue.\n\nThe issue only effects static files. If static files are served from a case-insensitive filesystem,\nsuch as default macOS setup, static files may be accessed by varying the case of the filename in the request.\nIf only lower-case (common default) filters are present in Shiro, they may be bypassed this way.\n\nShiro 2.1.0 and later has a new parameters to remediate this issue\nshiro.ini: filterChainResolver.caseInsensitive = true\napplication.properties: shiro.caseInsensitive=true\n\nShiro 3.0.0 and later makes this the default in\u00a0shiro.ini-based configurations.\nShiro 3.0.1 and later makes this the default in all configurations, including programmatic and Spring / Spring Boot."
        }
      ],
      "metrics": [
        {
          "other": {
            "content": {
              "text": "low"
            },
            "type": "Textual description of severity"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-289",
              "description": "CWE-289 Authentication Bypass by Alternate Name",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-20T09:44:32.338Z",
        "orgId": "f0158376-9dc2-43b6-827c-5f631a4d8d09",
        "shortName": "apache"
      },
      "references": [
        {
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://lists.apache.org/thread/5jjf0hnjcol58z2m5y255c7scz1lnp8k"
        }
      ],
      "source": {
        "discovery": "EXTERNAL"
      },
      "title": "Apache Shiro: Auth bypass when accessing static files only on case-insensitive filesystems",
      "x_generator": {
        "engine": "Vulnogram 0.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "f0158376-9dc2-43b6-827c-5f631a4d8d09",
    "assignerShortName": "apache",
    "cveId": "CVE-2026-23903",
    "datePublished": "2026-02-09T09:26:21.772Z",
    "dateReserved": "2026-01-19T01:14:40.103Z",
    "dateUpdated": "2026-08-20T09:44:32.338Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.