high
7.5
CWE
168
Advisory Published
Updated

CVE-2023-36843: Junos OS: SRX Series: The PFE will crash on receiving malformed SSL traffic when Sky ATP is enabled

First published: Thu Oct 12 2023(Updated: )

An Improper Handling of Inconsistent Special Elements vulnerability in the Junos Services Framework (jsf) module of Juniper Networks Junos OS allows an unauthenticated network based attacker to cause a crash in the Packet Forwarding Engine (pfe) and thereby resulting in a Denial of Service (DoS). Upon receiving malformed SSL traffic, the PFE crashes. A manual restart will be needed to recover the device. This issue only affects devices with Juniper Networks Advanced Threat Prevention (ATP) Cloud enabled with Encrypted Traffic Insights (configured via ‘security-metadata-streaming policy’). This issue affects Juniper Networks Junos OS: * All versions prior to 20.4R3-S8, 20.4R3-S9; * 21.1 version 21.1R1 and later versions; * 21.2 versions prior to 21.2R3-S6; * 21.3 versions prior to 21.3R3-S5; * 21.4 versions prior to 21.4R3-S5; * 22.1 versions prior to 22.1R3-S4; * 22.2 versions prior to 22.2R3-S2; * 22.3 versions prior to 22.3R2-S2, 22.3R3; * 22.4 versions prior to 22.4R2-S1, 22.4R3;

Credit: sirt@juniper.net

Affected SoftwareAffected VersionHow to fix
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=20.4-r3-s9
Juniper Junos=21.1-r1
Juniper Junos=21.1-r1-s1
Juniper Junos=21.1-r2
Juniper Junos=21.1-r2-s1
Juniper Junos=21.1-r2-s2
Juniper Junos=21.1-r3
Juniper Junos=21.1-r3-s1
Juniper Junos=21.1-r3-s2
Juniper Junos=21.1-r3-s3
Juniper Junos=21.1-r3-s4
Juniper Junos=21.1-r3-s5
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-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=22.2-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=22.3-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-r3
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-r3

Remedy

The following software releases have been updated to resolve this specific issue: Junos OS 20.4R3-S8, 21.2R3-S6, 21.3R3-S5, 21.4R3-S5, 22.1R3-S4, 22.2R3-S2, 22.3R2-S2, 22.3R3, 22.4R2-S1, 22.4R3, 23.1R2, 23.2R1, and all subsequent releases.

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2023-36843?

    CVE-2023-36843 is classified as a high severity vulnerability due to its potential to cause a Denial of Service.

  • How do I fix CVE-2023-36843?

    To mitigate CVE-2023-36843, update your Junos OS to a fixed version provided in Juniper's security advisory.

  • Which versions of Junos OS are affected by CVE-2023-36843?

    CVE-2023-36843 affects Junos OS versions prior to 20.4 and several subsequent releases up to 22.4.

  • What impact does CVE-2023-36843 have on network security?

    CVE-2023-36843 allows an unauthenticated attacker to crash the Packet Forwarding Engine, resulting in a Denial of Service.

  • Is authentication required to exploit CVE-2023-36843?

    No, CVE-2023-36843 can be exploited by an unauthenticated network-based attacker.

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