End-of-Life (EoL)

Discrete blocking

Prisma Cloud lets you create runtime rules that block discrete processes inside a container. It is an alternative to stopping an entire container when the violation of a runtime rule is detected.

Capabilities

Prisma Cloud runtime rules let you deny specific processes. When you specify the
Prevent
action in a runtime rule, Prisma Cloud blocks containers from running processes that are not defined in the model or the explicitly allowed processes list. The rest of the container continues to execute without disruption. The alternative to discrete blocking is container blocking, which stops the entire container when a denied process is detected.
The
Prevent
action is not supported on Debian 8.
Prisma Cloud also lets you deny file system writes to specific directories. Like the process rule, file system rules can be configured with the
Prevent
action, which blocks the creation and modification of any files in the specified directories. This mechanism is designed to prevent bad actors from writing certificates or binary attack tools to disk, all without killing the process that initiated the write or stopping the entire container.
The
Prevent
action for host file system rules requires a Linux kernel version 4.20 or later.
The
Prevent
action in file system rules is not supported when the Docker storage driver is set to aufs. It is supported for other storage drivers, such as devicemapper and overlay2. If you specify a
Prevent
action, but the storage driver does not support it, Prisma Cloud will respond with an alert and log the following message in Defender’s log: "Docker storage driver on host doesn’t support discrete file blocking"

Creating discrete blocking rules

Discrete blocking rules are created under
Defend > Runtime
.
Runtime rules have both a
Process
and a
File System
tab. These tabs let you configure the following effects:
  • Disable
    --
    Deactivates the runtime sensor.
  • Alert
    --
    Logs an event for a violation. For process rules, the process continues to run. For file system rules, the file system write is permitted.
  • Prevent
    --
    For process rules, the process is killed. For file system rules, the file write is prevented.
  • Block
    --
    Stops the entire container when a violation is detected.
  1. Open Console
  2. Go to
    Defend > Runtime > Container Policy
    .
  3. Click
    Add rule
    .
  4. In the
    General
    tab, specify a rule name.
  5. Click on the
    Processes
    tab.
  6. Under
    Effect
    , select
    Prevent
    .
  7. In
    Explicitly denied processes
    , specify a list of process names or MD5 hashes for processes that should be blocked from running.
  8. Click
    Save
    .

Recommended For You