CVE-2024-39561: Junos OS: SRX4600, SRX5000 Series: TCP packets with SYN/FIN or SYN/RST are transferred after enabling no-syn-check with Express Path
An Improper Check for Unusual or Exceptional Conditions vulnerability in the flow daemon (flowd) of Juniper Networks Junos OS on
SRX4600 and SRX5000 Series
allows an attacker to send TCP packets with
SYN/FIN or SYN/RST
flags, bypassing the expected blocking of these packets.
A TCP packet with SYN/FIN or SYN/RST should be dropped in flowd. However, when no-syn-check and Express Path are enabled, these TCP packets are unexpectedly transferred to the downstream network.
This issue affects Junos OS on SRX4600 and SRX5000 Series:
All versions before 21.2R3-S8, from 21.4 before 21.4R3-S7, from 22.1 before 22.1R3-S6, from 22.2 before 22.2R3-S4, from 22.3 before 22.3R3-S3, from 22.4 before 22.4R3-S2, from 23.2 before 23.2R2, from 23.4 before 23.4R1-S1, 23.4R2.
Affected Software
Remediation
Information
Event History
Frequently Asked Questions
What is the severity of CVE-2024-39561?
CVE-2024-39561 is considered a high severity vulnerability due to the potential for attackers to bypass security measures.
How does CVE-2024-39561 affect Junos OS?
CVE-2024-39561 affects the flow daemon in Junos OS, allowing attackers to send TCP packets with improper flags.
How do I fix CVE-2024-39561?
To fix CVE-2024-39561, upgrade to the patched versions of Junos OS as specified in the security advisory.
What devices are impacted by CVE-2024-39561?
CVE-2024-39561 impacts Juniper Networks SRX4600 and SRX5000 Series devices running vulnerable versions of Junos OS.
What are the implications of CVE-2024-39561 for network security?
CVE-2024-39561 can lead to unauthorized access and manipulation of network traffic, significantly compromising network security.