CVE-2021-43807: Opencast common HTTP Method Spoofing Vulnerability

HIGH
Advisory Identifier: GHSA-j4mm-7pj3-jf7v
CVSS 7.5
CWE-290
Published
Advisory Summary

CVE-2021-43807 is a HIGH (CVSS 7.5) http method spoofing vulnerability (CWE-290: Authentication Bypass by Spoofing) affecting Opencast common libraries in the Maven ecosystem. The issue involves http method spoofing. Remediation is available by upgrading affected packages to version 9.10.

CVE-2021-43807 at a Glance

CVE Identifier CVE-2021-43807
GHSA Identifier GHSA-j4mm-7pj3-jf7v
Severity HIGH
CVSS v3.1 Base Score 7.5
CWE Classification CWE-290: Authentication Bypass by Spoofing
Affected Product Opencast common
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 7.5

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H).

Attack Vector Network (AV:N)
Attack Complexity High (AC:H)
Privileges Required None (PR:N)
User Interaction Required (UI:R)
Scope Unchanged (S:U)
Confidentiality High (C:H)
Integrity High (I:H)
Availability High (A:H)

How to Fix CVE-2021-43807

To remediate this vulnerability, upgrade all affected Opencast common dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

org.opencastproject:opencast-common fixed: 9.10
<dependency>
    <groupId>org.opencastproject</groupId>
    <artifactId>opencast-common</artifactId>
    <version>9.10</version>
</dependency>
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release:

mvn dependency:tree -Dincludes=org.opencastproject

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2021-43807, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree -Dincludes=org.opencastproject

Analyze the terminal output to locate any version of Opencast common in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 9.10), your application is affected.

Note: The mvn dependency:tree -Dincludes=org.opencastproject command inspects the resolved dependency graph declared in your project's POM files; it does not perform automated security scanning or inspect runtime dynamic classpaths. Always verify runtime container classpaths and shaded JARs.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-290: Authentication Bypass by Spoofing, where this attack-focused weakness is caused by incorrectly implemented authentication schemes that are subject to spoofing attacks. In Opencast common, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

Opencast versions prior to 9.10 allow HTTP method spoofing, allowing to change the assumed HTTP method via URL parameter. This allows attackers to turn HTTP GET requests into PUT requests or an HTTP form to send DELETE requests. This bypasses restrictions otherwise put on these types of requests and aids in cross-site request forgery (CSRF) attacks, which would otherwise not be possible. ### Impact The vulnerability allows attackers to craft links or forms which may change the server state. For example, the following GET request would create a new user: ```sh % curl -i -u admin:opencast \ 'https://legacy.opencast.org/admin-ng/users/test.json?_method=PUT&username=test&password=attack' HTTP/2 200 … ``` If an admin is logged in to legacy.opencast.org and accidentally clicks this link, a user will silently be created. ### Patches This issue is fixed in Opencast 9.10 and 10.0. ### Workarounds You can mitigate the problem by setting the `SameSite=Strict` attribute for your cookies. If this is a viable option for you depends on your integrations. We strongly recommend updating in any case. ### References - [Fix for 10.0](https://github.com/opencast/opencast/commit/59cb6731067283e54f15462be38b6117d8b9ea8b#diff-9c5fb3d1b7e3b0f54bc5c4182965c4fe1f9023d449017cece3005d3f90e8e4d8) - [Fix for 9.10](https://github.com/opencast/opencast/commit/8f8271e1085f6f8e306c689d6a56b0bb8d076444) ### For more information If you have any questions or comments about this advisory: * Open an issue in [our issue tracker](https://github.com/opencast/opencast/issues) * Email us at [security@opencast.org](mailto:security@opencast.org)

CVE-2021-43807 Affected Opencast common Versions

1 component(s)
Fixed Versions:
9.10
Product / Package Ecosystem Affected Versions Fixed Version
org.opencastproject:opencast-common
Maven
< 9.10
9.10

References

Frequently Asked Questions

What is CVE-2021-43807?
CVE-2021-43807 is a security vulnerability in Opencast common involving HTTP Method Spoofing under CWE-290: Authentication Bypass by Spoofing.
Which Opencast common versions are affected?
Affected versions include releases prior to 9.10 across affected packages: org.opencastproject:opencast-common.
What version fixes CVE-2021-43807?
Upgrading to 9.10 (or the latest patched release for your respective branch) resolves the vulnerability.
Is opencast-common affected?
Yes, org.opencastproject:opencast-common is affected in releases prior to 9.10. Upgrade your dependency to 9.10 or later.
What is the CVSS score of CVE-2021-43807?
CVE-2021-43807 has a CVSS v3.1 base score of 7.5 (HIGH) with vector string CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H.
What CWE is associated with CVE-2021-43807?
CVE-2021-43807 is classified under CWE-290: Authentication Bypass by Spoofing (This attack-focused weakness is caused by incorrectly implemented authentication schemes that are subject to spoofing attacks.).
How can I check Maven dependencies for CVE-2021-43807?
Run the dependency tree command: 'mvn dependency:tree -Dincludes=org.opencastproject'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-j4mm-7pj3-jf7v",
  "modified" : "2022-01-04T18:54:12Z",
  "published" : "2021-12-14T21:43:00Z",
  "aliases" : [ "CVE-2021-43807" ],
  "summary" : "HTTP Method Spoofing",
  "details" : "Opencast versions prior to 9.10 allow HTTP method spoofing, allowing to change the assumed HTTP method via URL parameter. This allows  attackers to turn HTTP GET requests into PUT requests or an HTTP form to send DELETE requests. This bypasses restrictions otherwise put on these types of requests and aids in cross-site request forgery (CSRF) attacks, which would otherwise not be possible.\n\n### Impact\n\nThe vulnerability allows attackers to craft links or forms which may change the server state. For example, the following GET request would create a new user:\n\n```sh\n% curl -i -u admin:opencast \\\n  'https://legacy.opencast.org/admin-ng/users/test.json?_method=PUT&username=test&password=attack'\nHTTP/2 200\n…\n```\n\nIf an admin is logged in to legacy.opencast.org and accidentally clicks this link, a user will silently be created.\n\n\n### Patches\n\nThis issue is fixed in Opencast 9.10 and 10.0.\n\n### Workarounds\n\nYou can mitigate the problem by setting the `SameSite=Strict` attribute for your cookies. If this is a viable option for you depends on your integrations. We strongly recommend updating in any case.\n\n### References\n\n- [Fix for 10.0](https://github.com/opencast/opencast/commit/59cb6731067283e54f15462be38b6117d8b9ea8b#diff-9c5fb3d1b7e3b0f54bc5c4182965c4fe1f9023d449017cece3005d3f90e8e4d8)\n- [Fix for 9.10](https://github.com/opencast/opencast/commit/8f8271e1085f6f8e306c689d6a56b0bb8d076444)\n\n### For more information\n\nIf you have any questions or comments about this advisory:\n* Open an issue in [our issue tracker](https://github.com/opencast/opencast/issues)\n* Email us at [security@opencast.org](mailto:security@opencast.org)\n",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.opencastproject:opencast-common"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "9.10"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/opencast/opencast/security/advisories/GHSA-j4mm-7pj3-jf7v"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2021-43807"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/opencast/opencast/commit/59cb6731067283e54f15462be38b6117d8b9ea8b#diff-9c5fb3d1b7e3b0f54bc5c4182965c4fe1f9023d449017cece3005d3f90e8e4d8"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/opencast/opencast/commit/8f8271e1085f6f8e306c689d6a56b0bb8d076444"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/opencast/opencast"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-290" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2021-12-14T18:49:26Z",
    "nvd_published_at" : "2021-12-14T18:15:00Z"
  }
}