high
8.7
CWE
754
Advisory Published
Updated

CVE-2024-39540: Junos OS: SRX Series, and MX Series with SPC3: Specific valid TCP traffic can cause a pfe crash

First published: Thu Jul 11 2024(Updated: )

An Improper Check for Unusual or Exceptional Conditions vulnerability in the Packet Forwarding Engine (pfe) of Juniper Networks Junos OS on SRX Series, and MX Series with SPC3 allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS). When an affected device receives specific valid TCP traffic, the pfe crashes and restarts leading to a momentary but complete service outage. This issue affects Junos OS: 21.2 releases from 21.2R3-S5 before 21.2R3-S6. This issue does not affect earlier or later releases.

Credit: sirt@juniper.net

Affected SoftwareAffected VersionHow to fix
All of
Junos OS Evolved=21.2-r3-s5
Any of
Juniper CSRX
Juniper MX240
Juniper MX480
Juniper MX960
Juniper SRX100
Juniper SRX110
Juniper SRX1400
Juniper SRX1500
Juniper SRX1600
Juniper SRX210
Juniper SRX220
Juniper SRX2300
Juniper SRX240
Juniper SRX240H2
Juniper SRX240M
Juniper SRX300
Juniper SRX320
Juniper SRX340
Juniper SRX3400
Juniper SRX345
Juniper SRX3600
Juniper SRX380
Juniper SRX4000
Juniper SRX4100
Juniper SRX4200
Juniper SRX4300
Juniper SRX4600
Juniper SRX4700
Junos OS SRX 5000 Series
Juniper SRX5400
Juniper SRX550
Juniper SRX550
Juniper SRX550
Juniper SRX5600
Juniper SRX5800
Juniper SRX650
Juniper Networks Virtual SRX
Juniper JUNOS>=21.2R3-S5<21.2R3-S6

Remedy

The following software releases have been updated to resolve this specific issue: 21.2R3-S6.

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2024-39540?

    CVE-2024-39540 is classified as a critical vulnerability due to its potential to cause Denial-of-Service (DoS) attacks.

  • How do I fix CVE-2024-39540?

    To fix CVE-2024-39540, you should upgrade your Junos OS to a version later than 21.2R3-S6.

  • Who is affected by CVE-2024-39540?

    CVE-2024-39540 affects Juniper Networks Junos OS on SRX Series and MX Series devices with SPC3.

  • Can CVE-2024-39540 be exploited remotely?

    Yes, CVE-2024-39540 can be exploited by unauthenticated, network-based attackers.

  • What is the impact of CVE-2024-39540?

    The impact of CVE-2024-39540 is the potential for a Denial-of-Service (DoS), disrupting network availability.

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