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Security Advisories: MDE2OlNlY3VyaXR5QWR2aXNvcnlHSFNBLTIzeDQtbTg0Mi1mbXdm
Creation of Temporary File in Directory with Insecure Permissions in the OpenAPI-Generator online generator
Impact
On Unix like systems, the system's temporary directory is shared between all users on that system. A collocated user can observe the process of creating a temporary sub directory in the shared temporary directory and race to complete the creation of the temporary subdirectory.
This vulnerability is local privilege escalation because the contents of the outputFolder can be appended to by an attacker. As such, code written to this directory, when executed can be attacker controlled.
openapi-generator-online creates insecure temporary folders with File.createTempFile
during the code generation process. The insecure temporary folders store the auto-generated files which can be read and appended to by any users on the system.
Vulnerable Code
This vulnerability exists due to a race condition between the deletion of the randomly generated temporary file and the creation of the temporary directory.
File outputFolder = File.createTempFile("codegen-", "-tmp"); // Attacker knows the full path of the file that will be generated
// delete the file that was created
outputFolder.delete(); // Attacker sees file is deleted and begins a race to create their own directory before the code generator
// and make a directory of the same name
// SECURITY VULNERABILITY: Race Condition! - Attacker beats the code generator and now owns this directory
outputFolder.mkdir();
Patches
The issue has been patched by changing the underlying logic to use Files.createTempFile
and has been released in the v5.1.0 stable version.
This vulnerability has the same root cause as CVE-2021-21363 from the swagger-api/swagger-codegen
project as this project and that one both share the same original source tree.
See: https://github.com/swagger-api/swagger-codegen/security/advisories/GHSA-pc22-3g76-gm6j
For more information
If you have any questions or comments about this advisory:
- Open an issue in OpenAPI Generator Github repo
- Email us at [email protected]
JSON: https://advisories.ecosyste.ms/api/v1/advisories/MDE2OlNlY3VyaXR5QWR2aXNvcnlHSFNBLTIzeDQtbTg0Mi1mbXdm
Source: GitHub Advisory Database
Origin: Unspecified
Severity: Critical
Classification: General
Published: about 3 years ago
Updated: 11 months ago
CVSS Score: 9.4
CVSS vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Identifiers: GHSA-23x4-m842-fmwf, CVE-2021-21428
References:
- https://github.com/OpenAPITools/openapi-generator/security/advisories/GHSA-23x4-m842-fmwf
- https://github.com/swagger-api/swagger-codegen/security/advisories/GHSA-pc22-3g76-gm6j
- https://github.com/OpenAPITools/openapi-generator/pull/8788
- https://github.com/OpenAPITools/openapi-generator/blob/c6530519975341d7784a252132b2f0854f488901/modules/openapi-generator-online/src/main/java/org/openapitools/codegen/online/service/Generator.java#L184-L187
- https://nvd.nist.gov/vuln/detail/CVE-2021-21428
- https://github.com/advisories/GHSA-23x4-m842-fmwf
Blast Radius: 0.0
Affected Packages
maven:org.openapitools:openapi-generator-online
Dependent packages: 0Dependent repositories: 1
Downloads:
Affected Version Ranges: < 5.1.0
Fixed in: 5.1.0
All affected versions: 3.0.0, 3.0.1, 3.0.2, 3.0.3, 3.1.0, 3.1.1, 3.1.2, 3.2.0, 3.2.1, 3.2.2, 3.2.3, 3.3.0, 3.3.1, 3.3.2, 3.3.3, 3.3.4, 4.0.0, 4.0.1, 4.0.2, 4.0.3, 4.1.0, 4.1.1, 4.1.2, 4.1.3, 4.2.0, 4.2.1, 4.2.2, 4.2.3, 4.3.0, 4.3.1, 5.0.0, 5.0.1
All unaffected versions: 5.1.0, 5.1.1, 5.2.0, 5.2.1, 5.3.0, 5.3.1, 5.4.0, 6.0.0, 6.0.1, 6.1.0, 6.2.0, 6.2.1, 6.3.0, 6.4.0, 6.5.0, 6.6.0, 7.0.0, 7.0.1, 7.1.0, 7.2.0, 7.3.0, 7.4.0, 7.5.0