Junos OS RPD Race Condition Crash with BGP Multipath (CVE-2024-39554)
CVE-2024-39554 Published on July 10, 2024

Junos OS and Junos OS Evolved: BGP multipath incremental calculation is resulting in an rpd crash
A Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') vulnerability the Routing Protocol Daemon (rpd) of Juniper Networks Junos OS and Juniper Networks Junos OS Evolved allows an unauthenticated, network-based attacker to inject incremental routing updates when BGP multipath is enabled, causing rpd to crash and restart, resulting in a Denial of Service (DoS). Since this is a timing issue (race condition), the successful exploitation of this vulnerability is outside the attacker's control.  However, continued receipt and processing of this packet may create a sustained Denial of Service (DoS) condition. On all Junos OS and Junos OS Evolved platforms with BGP multipath enabled, a specific multipath calculation removes the original next hop from the multipath lead routes nexthop-set. When this change happens, multipath relies on certain internal timing to record the update.  Under certain circumstance and with specific timing, this could result in an rpd crash. This issue only affects systems with BGP multipath enabled. This issue affects: Junos OS: * All versions of 21.1 * from 21.2 before 21.2R3-S7, * from 21.4 before 21.4R3-S6, * from 22.1 before 22.1R3-S5, * from 22.2 before 22.2R3-S3, * from 22.3 before 22.3R3-S2, * from 22.4 before 22.4R3, * from 23.2 before 23.2R2. Junos OS Evolved: * All versions of 21.1-EVO, * All versions of 21.2-EVO, * from 21.4-EVO before 21.4R3-S6-EVO, * from 22.1-EVO before 22.1R3-S5-EVO, * from 22.2-EVO before 22.2R3-S3-EVO, * from 22.3-EVO before 22.3R3-S2-EVO, * from 22.4-EVO before 22.4R3-EVO, * from 23.2-EVO before 23.2R2-EVO. Versions of Junos OS before 21.1R1 are unaffected by this vulnerability. Versions of Junos OS Evolved before 21.1R1-EVO are unaffected by this vulnerability.

Vendor Advisory NVD

Vulnerability Analysis

CVE-2024-39554 is exploitable with network access, and does not require authorization privileges or user interaction. This vulnerability is consided to have a high level of attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality and integrity, and a high impact on availability.

Attack Vector:
NETWORK
Attack Complexity:
HIGH
Privileges Required:
NONE
User Interaction:
NONE
Scope:
UNCHANGED
Confidentiality Impact:
NONE
Integrity Impact:
NONE
Availability Impact:
HIGH

Weakness Type

What is a Race Condition Vulnerability?

The program contains a code sequence that can run concurrently with other code, and the code sequence requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence that is operating concurrently.

CVE-2024-39554 has been classified to as a Race Condition vulnerability or weakness.


Products Associated with CVE-2024-39554

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Juniper Networks Junos
 
Juniper Networks Junos Os Evolved
 

Affected Versions

Juniper Networks Junos OS: Juniper Networks Junos OS Evolved: juniper junos: juniper junos_os_evolved:

Exploit Probability

EPSS
0.42%
Percentile
61.67%

EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.