Palo Alto Networks Security Advisories / PAN-SA-2021-0002

PAN-SA-2021-0002 Informational: PAN-OS: NAT slipstreaming v1.0 and v2.0 attacks


Informational

Description

Network address translation (NAT) slipstreaming attacks v1.0 and v2.0 are network-based and they exploit weaknesses in web browsers and Application Level Gateways (ALGs) to expose internal network devices to an attacker.

The following threat prevention signatures prevent NAT slipstreaming attacks:

NAT Slipstreaming Detection (59667)

NAT Slipstreaming Detection (59668)

NAT Slipstreaming Detection (59669)

NAT Slipstreaming Detection (59671)

NAT Slipstreaming Detection (59672)

Product Status

VersionsAffectedUnaffected
PAN-OS NoneAll

Required Configuration for Exposure

Cannot be exposed.

Solution

The following threat prevention signatures block all known risks of NAT slipstreaming attacks:

NAT Slipstreaming Detection (59667)

NAT Slipstreaming Detection (59668)

NAT Slipstreaming Detection (59669)

NAT Slipstreaming Detection (59671)

NAT Slipstreaming Detection (59672)

A PAN-OS software upgrade is not required to mitigate NAT slipstreaming attacks.

Workarounds and Mitigations

If the threat prevention signatures cannot be applied or for additional protection:

Many web browsers include a security fix that prevents NAT slipstreaming attacks. These are known to include:

Chrome v87.0.4280.141 and later versions;

Microsoft’s Edge v87.0.664.75 and later versions;

Safari v14.0.3 and later versions;

Firefox v85.0 and later versions.

NAT Slipstreaming v2.0 attacks leverage H.323 and can be blocked by disallowing STUN application traffic in the PAN-OS appliance configuration.

Timeline

Added workaround for customers without a Threat Prevention subscription
Initial publication
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