[OSSA 2013-009] Validation of PKI tokens bypasses revocation check
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
OpenStack Identity (keystone) |
Invalid
|
Medium
|
Unassigned | ||
Folsom |
Fix Released
|
Medium
|
Dolph Mathews | ||
OpenStack Security Advisory |
Fix Released
|
Undecided
|
Thierry Carrez |
Bug Description
for PKI tokens, we are bypassing token.get_token() call and therefore skipping the “valid=True” check.
In Grizzly, this code is in keystone/
In Folsom, this code is in keystone/service.py
The if block bypasses the backend check. It is in the backend where tokens are checked for revocation.
def _get_token_
"""Returns a token if a valid one exists.
Optionally, limited to a token owned by a specific tenant.
"""
# TODO(termie): this stuff should probably be moved to middleware
if cms.is_
data = json.loads(
if belongs_to:
else:
return token_ref
The exposure is limited to people that are passing the whole PKI token back for validation via the web service.
This PKI tokens were supposed to be validated primarily via Crypto, but there is an option to validate them against the live server as well. It is only this last code path that is affected. It is unlikely to be triggered in Folsom, as people have to make a deliberate decision to use PKI tokens, and are unlikely to be validating them against the Keystone server.
Remote services can choose to pass a Hash of the PKI token to the validate Web API, which web services are likely to do, as the Hash is short enough to fit in a cookie. The Hash is then it looked up using the backend get_token() behavior and works correctly.
It does not effect the keystone calls that first require validating the token. For example if a user runs tenant_list against their own account, using a PKI token, they do
token_ref = self.token_
This was discovered by Guang Yee.
Related branches
- Openstack Ubuntu Testers: Pending requested
-
Diff: 169 lines (+135/-1)3 files modifieddebian/changelog (+27/-1)
debian/patches/CVE-2013-1865.patch (+107/-0)
debian/patches/series (+1/-0)
CVE References
information type: | Private Security → Public Security |
summary: |
- Validation of PKI tokens bypasses revocation check + [OSSA 2013-009] Validation of PKI tokens bypasses revocation check |
Changed in ossa: | |
assignee: | nobody → Thierry Carrez (ttx) |
status: | New → Fix Released |
Isn't the benefit of PKI tokens that you don't have to validate them against the Keystone server directly ? Is that direct check called by clients anywhere (think when Nova receives a PKI token) ? On the other hand, would the crypto validation check revocation ? I'm trying to see if this is worth an advisory, or if it's really a corner case. Opinions welcome.