CVE-2023-36841

Junos OS: MX Series: Receipt of malformed TCP traffic will cause a Denial of Service

Description

An Improper Check for Unusual or Exceptional Conditions vulnerability in the Packet Forwarding Engine (pfe) of Juniper Networks Junos OS on MX Series allows a unauthenticated network-based attacker to cause an infinite loop, resulting in a Denial of Service (DoS). An attacker who sends malformed TCP traffic via an interface configured with PPPoE, causes an infinite loop on the respective PFE. This results in consuming all resources and a manual restart is needed to recover. This issue affects interfaces with PPPoE configured and tcp-mss enabled. This issue affects Juniper Networks Junos OS * All versions prior to 20.4R3-S7; * 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-S3; * 22.1 versions prior to 22.1R3-S4; * 22.2 versions prior to 22.2R3; * 22.3 versions prior to 22.3R2-S2; * 22.4 versions prior to 22.4R2;

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: Junos OS 20.4R3-S7, 21.2R3-S6, 21.4R3-S3, 22.1R3-S4, 22.2R3, 22.3R2-S2, 22.3R3, 22.4R2, 23.2R1, and all subsequent releases.

Workaround:

  • There are no known workarounds for this issue.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.13%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2023-36841?
CVE-2023-36841 has been scored as a high severity vulnerability.
How to fix CVE-2023-36841?
To fix CVE-2023-36841: The following software releases have been updated to resolve this specific issue: Junos OS 20.4R3-S7, 21.2R3-S6, 21.4R3-S3, 22.1R3-S4, 22.2R3, 22.3R2-S2, 22.3R3, 22.4R2, 23.2R1, and all subsequent releases.
Is CVE-2023-36841 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-36841 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-2023-36841?
CVE-2023-36841 affects Juniper Networks Junos OS.
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