CVE-2020-1999: PAN-OS: Threat signatures are evaded by specifically crafted packets

Published Nov 12, 2020
·
Updated

A vulnerability exists in the Palo Alto Network PAN-OS signature-based threat detection engine that allows an attacker to communicate with devices in the network in a way that is not analyzed for threats by sending data through specifically crafted TCP packets. This technique evades signature-based threat detection. This issue impacts: PAN-OS 8.1 versions earlier than 8.1.17; PAN-OS 9.0 versions earlier than 9.0.11; PAN-OS 9.1 versions earlier than 9.1.5; All versions of PAN-OS 7.1 and PAN-OS 8.0.

Affected Software

5 affected components
Palo Alto Networks PAN-OS>=7.1.0<=7.1.26
Palo Alto Networks PAN-OS>=8.0.0<=8.0.20
Palo Alto Networks PAN-OS>=8.1.0<8.1.17
Palo Alto Networks PAN-OS>=9.0.0<9.0.11
Palo Alto Networks PAN-OS>=9.1.0<9.1.5

Remediation

Information

This issue is fixed in PAN-OS 8.1.17, PAN-OS 9.0.11, PAN-OS 9.1.5, and all later PAN-OS versions.

Event History

Nov 12, 2020
CVE Published
via MITRE·12:05 AM
Data Sourced
via MITRE·12:05 AM
RemedyDescriptionSeverityWeakness

Frequently Asked Questions

1

What is CVE-2020-1999?

CVE-2020-1999 is a vulnerability that exists in the Palo Alto Network PAN-OS signature-based threat detection engine.

2

How does CVE-2020-1999 work?

CVE-2020-1999 allows an attacker to communicate with devices in the network by sending data through specifically crafted TCP packets.

3

Which software versions are affected by CVE-2020-1999?

Palo Alto Network PAN-OS versions 7.1.0 to 7.1.26, 8.0.0 to 8.0.20, 8.1.0 to 8.1.17, 9.0.0 to 9.0.11, and 9.1.0 to 9.1.5 are affected by CVE-2020-1999.

4

What is the severity of CVE-2020-1999?

CVE-2020-1999 has a severity rating of 5.3, which is considered medium.

5

How can I mitigate CVE-2020-1999?

Palo Alto Networks has released a security advisory and software updates to address CVE-2020-1999. It is recommended to update to the latest version of PAN-OS.

Contact

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