diff options
Diffstat (limited to 'SECURITY')
| -rw-r--r-- | SECURITY | 20 |
1 files changed, 13 insertions, 7 deletions
@@ -18,21 +18,27 @@ Two tests pass arguments from the configuration file to the shell: ping http/https -The hostname used to ping, and the URL for web-tests, are both passed directly to the shell with no encoding or sanitizing. The only issue is that the hostnames must match the following regular expression: +The hostname used to ping, and the URL for web-tests, are both passed directly to the shell assuming they match the following regular expression: ^([^\s]+)\s+ -The following configuration file allows the specified command to be executed, as the user running the dequeue tool, via the shell: +So the following configuration file potentially allows a command to be executed by our worker: $(/home/steve/hg/custodian/exploit.sh) must ping otherwise "Owned". -Given that anybody who can talk to the beanstalkd server can submit JSON-encoded-jobs we have no solution here which involves sanity-checking the parsed-hostnames. Instead we much either restrict submissions to signed ones, or we must remove the following from hostnames: + http://$(/tmp/exploit.sh)/ must run http with status 200 otherwise "Owned". - $( ... ) - Expansion. - ` .. ` - Backticks. - ; .. - Sub-commands. +Given that anybody who can talk to the beanstalkd server can submit JSON-encoded-jobs we cannot rely on catching this solely in the parser. -That has not yet been done, but it is definitely on the map. +For the moment we've solved the case of the ping-exploitation, because the +valid hostnames passed there are [a-z0-9.-]. We've not yet sanitized URLs +because that is a harder job. + +In the case of the ping-test we've done both levels of testing: + + * Test the hostname is valid priorer to executing the shell. + + * Ensure the hostname is valid before adding the job to the queue. |