CVE-2024-39559: high-severity vulnerability in Juniper Networks Junos OS Evolved
Junos OS Evolved: Receipt of a specific TCP packet may result in a system crash (vmcore) on dual RE systems with NSR enabled
Published · Updated
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.2epss 0.4%
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.
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/R:A
Affected products
Juniper Networks · Junos OS EvolvedRelated CVEs — Juniper Networks Junos OS Evolved
In the same product, most dangerous first.
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