Comment 0 for bug 1613901

While doing some testing on Keystone using Syntribos (https://github.com/openstack/syntribos), our team (myself, Michael Dong, Rahul U Nair, Vinay Potluri, Aastha Dixit, and Khanak Nangia) noticed that we got 500 status codes when the string "..%c0%af" was inserted in various places in the URL for different types of requests.

Here are some examples:

=========

DELETE /v3/policies/..%c0%af HTTP/1.1
Host: [REDACTED]:5000
Connection: close
Accept-Encoding: gzip, deflate
Accept: application/json
User-Agent: python-requests/2.11.0
X-Auth-Token: [REDACTED]
Content-Length: 0

HTTP/1.1 500 Internal Server Error
Date: Tue, 16 Aug 2016 22:04:27 GMT
Server: Apache/2.4.7 (Ubuntu)
Vary: X-Auth-Token
X-Distribution: Ubuntu
x-openstack-request-id: req-238fd5a9-be45-41f2-893a-97b513b27af3
Content-Length: 143
Connection: close
Content-Type: application/json

{"error": {"message": "An unexpected error prevented the server from fulfilling your request.", "code": 500, "title": "Internal Server Error"}}

=========

PATCH /v3/policies/..%c0%af HTTP/1.1
Host: [REDACTED]:5000
Connection: close
Accept-Encoding: gzip, deflate
Accept: application/json
User-Agent: python-requests/2.11.0
Content-type: application/json
X-Auth-Token: [REDACTED]
Content-Length: 70

{"type": "--serialization-mime-type--", "blob": "--serialized-blob--"}

HTTP/1.1 500 Internal Server Error
Date: Tue, 16 Aug 2016 22:05:36 GMT
Server: Apache/2.4.7 (Ubuntu)
Vary: X-Auth-Token
X-Distribution: Ubuntu
x-openstack-request-id: req-57a41600-02b4-4d2a-b3e9-40f7724d65f2
Content-Length: 143
Connection: close
Content-Type: application/json

{"error": {"message": "An unexpected error prevented the server from fulfilling your request.", "code": 500, "title": "Internal Server Error"}}

=========

GET /v3/domains/0426ac1e48f642ef9544c2251e07e261/groups/..%c0%af/roles HTTP/1.1
Host: [REDACTED]:5000
Connection: close
Accept-Encoding: gzip, deflate
Accept: application/json
User-Agent: python-requests/2.11.0
X-Auth-Token: [REDACTED]

HTTP/1.1 500 Internal Server Error
Date: Tue, 16 Aug 2016 22:07:09 GMT
Server: Apache/2.4.7 (Ubuntu)
Vary: X-Auth-Token
X-Distribution: Ubuntu
x-openstack-request-id: req-02313f77-63c6-4aa8-a87e-e3d2a13ad6b7
Content-Length: 143
Connection: close
Content-Type: application/json

{"error": {"message": "An unexpected error prevented the server from fulfilling your request.", "code": 500, "title": "Internal Server Error"}}

=========

I've marked this as a security issue as a precaution in case it turns out that there is a more serious vulnerability underlying these errors. We have no reason to suspect that there is a greater vulnerability at this time, but given the many endpoints this seems to affect, I figured caution was worthwhile since this may be a framework-wide issue. Feel free to make this public if it is determined not to be security-impacting.

Here is a (possibly incomplete) list of affected endpoints. Inserting the string "..%c0%af" in any or all of the spots labeled "HERE" should yield a 500 error. As you can see, virtually all v3 endpoints exhibit this behavior.

=========

[GET|PATCH|DELETE] /v3/endpoints/[HERE]

[GET|PATCH] /v3/domains/[HERE]
GET /v3/domains/[HERE]/groups/[HERE]/roles
[HEAD|PUT|DELETE] /v3/domains/[HERE]/groups/[HERE]/roles/[HERE]
GET /v3/domains/[HERE]/users/[HERE]/roles
[HEAD|DELETE] /v3/domains/[HERE]/users/[HERE]/roles/[HERE]

[GET|PATCH|DELETE] /v3/groups/[HERE]
[HEAD|PUT|DELETE] /v3/groups[HERE]/users/[HERE]

[POST|DELETE] /v3/keys/[HERE]

[GET|PATCH|DELETE] /v3/policies/[HERE]
[GET|PUT|DELETE] /v3/policies/[HERE]/OS-ENDPOINT-POLICY/endpoints/[HERE]
[GET|HEAD] /v3/policies/[HERE]/OS-ENDPOINT-POLICY/policy
[GET|PUT|DELETE] /v3/policies/[HERE]/OS-ENDPOINT-POLICY/services/[HERE]
[PUT|DELETE] /v3/policies/[HERE]/OS-ENDPOINT-POLICY/services/[HERE]
[GET|PUT|DELETE] /v3/policies/[HERE]/OS-ENDPOINT-POLICY/services/regions/[HERE]

[GET|PATCH|DELETE] /v3/projects/[HERE]
[DELETE|PATCH] /v3/projects/[HERE]/cascade
GET /v3/projects/[HERE]/groups/[HERE]/roles
GET /v3/projects/[HERE]/users/[HERE]/roles
[HEAD|PUT|DELETE] /v3/projects/[HERE]/groups/[HERE]/roles/[HERE]

[GET|PATCH|DELETE] /v3/regions/[HERE]

[PATCH|DELETE] /v3/roles/[HERE]

[GET|PATCH|DELETE] /v3/services/[HERE]

[GET|PATCH|DELETE] /v3/users/[HERE]
GET /v3/users/[HERE]/groups
POST /v3/users/[HERE]/password
GET /v3/users/[HERE]/projects

GET /v3/OS-OAUTH1/users/[HERE]/access_tokens/[HERE]/roles/[HERE]
[GET|PATCH|DELETE] /v3/OS-OAUTH1/consumers/[HERE]
[GET|DELETE] /v3/OS-OAUTH1/users/[HERE]/access_tokens/[HERE]