[
https://issues.apache.org/jira/browse/ZOOKEEPER-2693?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15881932#comment-15881932
]
Rakesh R commented on ZOOKEEPER-2693:
-------------------------------------
I'm trying an attempt to unblock 3.4.10 and 3.5.3 releases. Following are few
proposals to make the release happen by including the reported issue.
*3.4.10 requirement:*
Expose whitelist configuration with the default values,
{{4lw.commands.whitelist=ruok,srvr,crst,srst,isro,mntr}}
Also, properly documenting the {{Publicly accessible deployment}} part from the
current PR_179 changes.
*3.5.3 requirement:*
IMHO, there are two possible proposals:
# +Proposal-1)+
Expose whitelist configuration with the default values,
{{4lw.commands.whitelist=srvr,isro}}
Also, recommend users to use admin server rather than 4lw cmds
considering that 4lw will deprecated in future.
Then, later in 3.5.4, we could make this whitelist <empty> and while
deprecating will replace srvr, isro calls with better solution. That way, we
would get enough time to think about better solutions.
# +Proposal-2)+
Expose whitelist configuration with the empty default value,
{{4lw.commands.whitelist=<empty>}}
* (a) How about zkServer.sh usage of "srvr" can be achieved like,
Introduce a new admin API, admin#getServerStatus("host:port"), which
will return running stat of that server(probably, the same string format where
srvr command is returning)
{code}
"version=<full_version>
read_only=false
server_stats=<statistics>
node_count=<count>"
{code}
* (b) Client#pingRwServer=> Just a plain thought, probably, readonly
client code can internally tries to establish new client session with all other
servers round robin fashion. Then, check whether that the connected server is
in {{rw}} mode and act upon.
> DOS attack on wchp/wchc four letter words (4lw)
> -----------------------------------------------
>
> Key: ZOOKEEPER-2693
> URL: https://issues.apache.org/jira/browse/ZOOKEEPER-2693
> Project: ZooKeeper
> Issue Type: Bug
> Components: security, server
> Affects Versions: 3.4.0, 3.5.1, 3.5.2
> Reporter: Patrick Hunt
> Assignee: Michael Han
> Priority: Blocker
> Fix For: 3.4.10, 3.5.3
>
> Attachments: ZOOKEEPER-2693-01.patch
>
>
> The wchp/wchc four letter words can be exploited in a DOS attack on the ZK
> client port - typically 2181. The following POC attack was recently published
> on the web:
> https://webcache.googleusercontent.com/search?q=cache:_CNGIz10PRYJ:https://www.exploit-db.com/exploits/41277/+&cd=14&hl=en&ct=clnk&gl=us
> The most straightforward way to block this attack is to not allow access to
> the client port to non-trusted clients - i.e. firewall the ZooKeeper service
> and only allow access to trusted applications using it for coordination.
--
This message was sent by Atlassian JIRA
(v6.3.15#6346)
