CVE-2023-36843

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

Description

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;

Remediation

Solution:

  • 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.

Workaround:

  • Removing the security-metadata-streaming policy from the configuration stops the issue.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.09%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2023-36843?
CVE-2023-36843 has been scored as a high severity vulnerability.
How to fix CVE-2023-36843?
To fix CVE-2023-36843: 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.
Is CVE-2023-36843 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-36843 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-36843?
CVE-2023-36843 affects Juniper Networks Junos OS.
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