CVE-2024-21606: Junos OS: SRX Series: When "tcp-encap" is configured and specific packets are received flowd will crash

Published Jan 12, 2024
·
Updated

A Double Free vulnerability in the flow processing daemon (flowd) of Juniper Networks Junos OS on SRX Series allows a network-based, unauthenticated attacker to cause a Denial of Service (DoS).

In a remote access VPN scenario, if a "tcp-encap-profile" is configured and a sequence of specific packets is received, a flowd crash and restart will be observed.

This issue affects Juniper Networks Junos OS on SRX Series:

All versions earlier than 20.4R3-S8; 21.2 versions earlier than 21.2R3-S6; 21.3 versions earlier than 21.3R3-S5; 21.4 versions earlier than 21.4R3-S5; 22.1 versions earlier than 22.1R3-S3; 22.2 versions earlier than 22.2R3-S3; 22.3 versions earlier than 22.3R3-S1; 22.4 versions earlier than 22.4R2-S2, 22.4R3.

Affected Software

118 affected components
All of the following
Any of the following
Juniper Junos<20.4
Juniper Junos=20.4
Juniper Junos=20.4-r1
Juniper Junos=20.4-r1-s1
Juniper Junos=20.4-r2
Juniper Junos=20.4-r2-s1
Juniper Junos=20.4-r2-s2
Juniper Junos=20.4-r3
Juniper Junos=20.4-r3-s1
Juniper Junos=20.4-r3-s2
Juniper Junos=20.4-r3-s3
Juniper Junos=20.4-r3-s4
Juniper Junos=20.4-r3-s5
Juniper Junos=20.4-r3-s6
Juniper Junos=20.4-r3-s7
Juniper Junos=21.2
Juniper Junos=21.2-r1
Juniper Junos=21.2-r1-s1
Juniper Junos=21.2-r1-s2
Juniper Junos=21.2-r2
Juniper Junos=21.2-r2-s1
Juniper Junos=21.2-r2-s2
Juniper Junos=21.2-r3
Juniper Junos=21.2-r3-s1
Juniper Junos=21.2-r3-s2
Juniper Junos=21.2-r3-s3
Juniper Junos=21.2-r3-s4
Juniper Junos=21.2-r3-s5
Juniper Junos=21.3
Juniper Junos=21.3-r1
Juniper Junos=21.3-r1-s1
Juniper Junos=21.3-r1-s2
Juniper Junos=21.3-r2
Juniper Junos=21.3-r2-s1
Juniper Junos=21.3-r2-s2
Juniper Junos=21.3-r3
Juniper Junos=21.3-r3-s1
Juniper Junos=21.3-r3-s2
Juniper Junos=21.3-r3-s3
Juniper Junos=21.3-r3-s4
Juniper Junos=21.4
Juniper Junos=21.4-r1
Juniper Junos=21.4-r1-s1
Juniper Junos=21.4-r1-s2
Juniper Junos=21.4-r2
Juniper Junos=21.4-r2-s1
Juniper Junos=21.4-r2-s2
Juniper Junos=21.4-r3
Juniper Junos=21.4-r3-s1
Juniper Junos=21.4-r3-s2
Juniper Junos=21.4-r3-s3
Juniper Junos=21.4-r3-s4
Juniper Junos=22.1
Juniper Junos=22.1-r1
Juniper Junos=22.1-r1-s1
Juniper Junos=22.1-r1-s2
Juniper Junos=22.1-r2
Juniper Junos=22.1-r2-s1
Juniper Junos=22.1-r2-s2
Juniper Junos=22.1-r3
Juniper Junos=22.1-r3-s1
Juniper Junos=22.1-r3-s2
Juniper Junos=22.2
Juniper Junos=22.2-r1
Juniper Junos=22.2-r1-s1
Juniper Junos=22.2-r1-s2
Juniper Junos=22.2-r2
Juniper Junos=22.2-r2-s1
Juniper Junos=22.2-r2-s2
Juniper Junos=22.2-r3
Juniper Junos=22.2-r3-s1
Juniper Junos=22.2-r3-s2
Juniper Junos=22.3
Juniper Junos=22.3-r1
Juniper Junos=22.3-r1-s1
Juniper Junos=22.3-r1-s2
Juniper Junos=22.3-r2
Juniper Junos=22.3-r2-s1
Juniper Junos=22.3-r2-s2
Juniper Junos=22.3-r3
Juniper Junos=22.4
Juniper Junos=22.4-r1
Juniper Junos=22.4-r1-s1
Juniper Junos=22.4-r1-s2
Juniper Junos=22.4-r2
Juniper Junos=22.4-r2-s1
Any of the following
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
Juniper SRX5000
Juniper SRX5400
Juniper SRX550
Juniper Srx550 Hm
Juniper SRX550m
Juniper SRX5600
Juniper SRX5800
Juniper SRX650

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Juniper Networks Junos OS (SRX Series) to a version that resolves this vulnerability.

    Fixed in 20.4R3-S8
  2. Upgrade

    Upgrade Juniper Networks Junos OS (SRX Series) to a version that resolves this vulnerability.

    Fixed in 21.2R3-S6
  3. Upgrade

    Upgrade Juniper Networks Junos OS (SRX Series) to a version that resolves this vulnerability.

    Fixed in 21.3R3-S5
  4. Upgrade

    Upgrade Juniper Networks Junos OS (SRX Series) to a version that resolves this vulnerability.

    Fixed in 21.4R3-S5
  5. Upgrade

    Upgrade Juniper Networks Junos OS (SRX Series) to a version that resolves this vulnerability.

    Fixed in 22.1R3-S3
  6. Upgrade

    Upgrade Juniper Networks Junos OS (SRX Series) to a version that resolves this vulnerability.

    Fixed in 22.2R3-S3
  7. Upgrade

    Upgrade Juniper Networks Junos OS (SRX Series) to a version that resolves this vulnerability.

    Fixed in 22.3R3-S1
  8. Upgrade

    Upgrade Juniper Networks Junos OS (SRX Series) to a version that resolves this vulnerability.

    Fixed in 22.4R2-S2
  9. Upgrade

    Upgrade Juniper Networks Junos OS (SRX Series) to a version that resolves this vulnerability.

    Fixed in 22.4R3
  10. Upgrade

    Upgrade Juniper Networks Junos OS (SRX Series) to a version that resolves this vulnerability.

    Fixed in 23.2R1

Event History

Jan 12, 2024
CVE Published
via MITRE·12:54 AM
Data Sourced
via MITRE·12:54 AM
RemedyDescriptionSeverityWeakness
Data Sourced
via NVD·01:15 AM
DescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is the severity of CVE-2024-21606?

CVE-2024-21606 has a high severity rating, classified as a Denial of Service (DoS) vulnerability.

2

How do I fix CVE-2024-21606?

To mitigate CVE-2024-21606, upgrade to a patched version of Junos OS that addresses this vulnerability.

3

Which versions of Junos OS are affected by CVE-2024-21606?

CVE-2024-21606 affects multiple versions of Junos OS, specifically those prior to version 20.4 and specific releases within the 20.4 and 21.x series.

4

Can CVE-2024-21606 be exploited remotely?

Yes, CVE-2024-21606 can be exploited by network-based, unauthenticated attackers.

5

What impact does CVE-2024-21606 have on network devices?

The impact of CVE-2024-21606 can result in a Denial of Service (DoS) affecting the availability of network services.

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