Junos Os Evolved CVE-2024-39559

Q: What is the CVSS score of CVE-2024-39559?

CVE-2024-39559 has a CVSS 4.0 base score of 8.2 (High). CVSS vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:A/V:X/RE:X/U:X. EPSS exploitation probability: 0.4%.

HIGH

Improper Check for Unusual or Exceptional Conditions (CWE-754)

2024-07-10 sirt@juniper.net

Juniper Denial Of Service Junos Os Evolved

8.2

CVSS 4.0 · Vendor: juniper

Severity by source

Vendor (juniper) PRIMARY

8.2 HIGH

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:A/V:X/RE:X/U:X

Primary rating from Vendor (juniper) · only source for this CVE.

CVSS VectorVendor: juniper

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:A/V:X/RE:X/U:X

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Lifecycle Timeline

CVE Published

Jul 10, 2024 - 23:15 cve.org

HIGH 8.2

DescriptionCVE.org

An Improper Check for Unusual or Exceptional Conditions vulnerability in packet processing of Juniper Networks Junos OS Evolved may allow a network-based unauthenticated attacker to crash the device (vmcore) by sending a specific TCP packet over an established TCP session with MD5 authentication enabled, destined to an accessible port on the device, resulting in a Denial of Service (DoS). The receipt of this packet must occur within a specific timing window outside the attacker's control (i.e., race condition).

Continued receipt and processing of this packet will create a sustained Denial of Service (DoS) condition.

This issue only affects dual RE systems with Nonstop Active Routing (NSR) enabled. Exploitation can only occur over TCP sessions with MD5 authentication enabled (e.g., BGP with MD5 authentication).

This issue affects Junos OS Evolved:

All versions before 21.2R3-S8-EVO,
from 21.4-EVO before 21.4R3-S6-EVO,
from 22.1-EVO before 22.1R3-S4-EVO,
from 22.2-EVO before 22.2R3-S4-EVO,
from 22.3-EVO before 22.3R3-S3-EVO,
from 22.4-EVO before 22.4R2-S2-EVO, 22.4R3-EVO.

AnalysisAI

An Improper Check for Unusual or Exceptional Conditions vulnerability in packet processing of Juniper Networks Junos OS Evolved may allow a network-based unauthenticated attacker to crash the device. Rated high severity (CVSS 8.2), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.

Technical ContextAI

This vulnerability is classified under CWE-754. An Improper Check for Unusual or Exceptional Conditions vulnerability in packet processing of Juniper Networks Junos OS Evolved may allow a network-based unauthenticated attacker to crash the device (vmcore) by sending a specific TCP packet over an established TCP session with MD5 authentication enabled, destined to an accessible port on the device, resulting in a Denial of Service (DoS). The receipt of this packet must occur within a specific timing window outside the attacker's control (i.e., race condition). Continued receipt and processing of this packet will create a sustained Denial of Service (DoS) condition. This issue only affects dual RE systems with Nonstop Active Routing (NSR) enabled. Exploitation can only occur over TCP sessions with MD5 authentication enabled (e.g., BGP with MD5 authentication).2R3-S8-EVO, * from 21.4-EVO before 21.4R3-S6-EVO, * from 22.1-EVO before 22.1R3-S4-EVO, * from 22.2-EVO before 22.2R3-S4-EVO, * from 22.3-EVO before 22.3R3-S3-EVO, * from 22.4-EVO before 22.4R2-S2-EVO, 22.4R3-EVO. Affected products include: Juniper Junos Os Evolved. Version information: before 21.2.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.