CVE-2025-21597

Junos OS and Junos OS Evolved: When BGP rib-sharding and update-threading are configured and a peer flaps, an rpd core is observed

Severity Score

6.0

*CVSS v4

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

Track

*SSVC

Descriptions

MITRE
TN

An Improper Check for Unusual or Exceptional Conditions vulnerability in routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, logically adjacent BGP peer to cause Denial of Service (DoS). On all Junos OS and Junos OS Evolved platforms, when BGP rib-sharding and update-threading are configured, and a BGP peer flap is done with specific timing, rpd crashes and restarts. Continuous peer flapping at specific time intervals will result in a sustained Denial of Service (DoS) condition. This issue affects eBGP and iBGP, in both IPv4 and IPv6 implementations. This issue requires a remote attacker to have at least one established BGP session. The issue can occur with or without logical-systems enabled. This issue affects:
Junos OS: * All versions before 20.4R3-S8, * 21.2 versions before 21.2R3-S6, * 21.3 versions before 21.3R3-S5, * 21.4 versions before 21.4R3-S4, * 22.1 versions before 22.1R3-S3, * 22.2 versions before 22.2R3-S1, * 22.3 versions before 22.3R3, * 22.4 versions before 22.4R3. Junos OS Evolved: * All versions before 21.2R3-S6-EVO, * 21.3-EVO versions before 21.3R3-S5-EVO, * 21.4-EVO versions before 21.4R3-S4-EVO, * 22.1-EVO versions before 22.1R3-S3-EVO, * 22.2-EVO versions before :22.2R3-S1-EVO, * 22.3-EVO versions before 22.3R3-EVO, * 22.4-EVO versions before 22.4R3-EVO.

An Improper Check for Unusual or Exceptional Conditions vulnerability in routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, logically adjacent BGP peer to cause Denial of Service (DoS). On all Junos OS and Junos OS Evolved platforms, when BGP rib-sharding and update-threading are configured, and a BGP peer flap is done with specific timing, rpd crashes and restarts. Continuous peer flapping at specific time intervals will result in a sustained Denial of Service (DoS) condition. This issue affects eBGP and iBGP, in both IPv4 and IPv6 implementations. This issue requires a remote attacker to have at least one established BGP session. The issue can occur with or without logical-systems enabled. This issue affects: Junos OS: * All versions before 20.4R3-S8, * 21.2 versions before 21.2R3-S6, * 21.3 versions before 21.3R3-S5, * 21.4 versions before 21.4R3-S4, * 22.1 versions before 22.1R3-S3, * 22.2 versions before 22.2R3-S1, * 22.3 versions before 22.3R3, * 22.4 versions before 22.4R3. Junos OS Evolved: * All versions before 21.2R3-S6-EVO, * 21.3-EVO versions before 21.3R3-S5-EVO, * 21.4-EVO versions before 21.4R3-S4-EVO, * 22.1-EVO versions before 22.1R3-S3-EVO, * 22.2-EVO versions before :22.2R3-S1-EVO, * 22.3-EVO versions before 22.3R3-EVO, * 22.4-EVO versions before 22.4R3-EVO.

*Credits: N/A

CVSS Scores

Attack Vector

Adjacent

Attack Complexity

Low

Attack Requirements

Present

Privileges Required

None

User Interaction

None

System

Vulnerable | Subsequent

Confidentiality

None

Integrity

None

Availability

High

Low

Attack Vector

Adjacent

Attack Complexity

High

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Attack Vector

Adjacent

Attack Complexity

High

Authentication

None

Confidentiality

None

Integrity

None

Availability

Complete

* Common Vulnerability Scoring System

SSVC

Decision:Track

Exploitation

None

Automatable

Tech. Impact

Partial

* Organization's Worst-case Scenario

Timeline

2024-12-26 CVE Reserved
2025-04-09 CVE Published
2025-04-10 CVE Updated
2025-04-10 EPSS Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-754: Improper Check for Unusual or Exceptional Conditions

CAPEC

References (1)

URL	Tag	Source

URL	Date	SRC

URL	Date	SRC

URL	Date	SRC
https://kb.juniper.net/JSA96451	2025-04-10

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Juniper Networks Search vendor "Juniper Networks"		Junos OS Search vendor "Juniper Networks" for product "Junos OS"				< 20.4R3-S8 Search vendor "Juniper Networks" for product "Junos OS" and version " < 20.4R3-S8"		en		Affected
Juniper Networks Search vendor "Juniper Networks"		Junos OS Search vendor "Juniper Networks" for product "Junos OS"				>= 21.2 < 21.2R3-S6 Search vendor "Juniper Networks" for product "Junos OS" and version " >= 21.2 < 21.2R3-S6"		en		Affected
Juniper Networks Search vendor "Juniper Networks"		Junos OS Search vendor "Juniper Networks" for product "Junos OS"				>= 21.3 < 21.3R3-S5 Search vendor "Juniper Networks" for product "Junos OS" and version " >= 21.3 < 21.3R3-S5"		en		Affected
Juniper Networks Search vendor "Juniper Networks"		Junos OS Search vendor "Juniper Networks" for product "Junos OS"				>= 21.4 < 21.4R3-S4 Search vendor "Juniper Networks" for product "Junos OS" and version " >= 21.4 < 21.4R3-S4"		en		Affected
Juniper Networks Search vendor "Juniper Networks"		Junos OS Search vendor "Juniper Networks" for product "Junos OS"				>= 22.1 < 22.1R3-S3 Search vendor "Juniper Networks" for product "Junos OS" and version " >= 22.1 < 22.1R3-S3"		en		Affected
Juniper Networks Search vendor "Juniper Networks"		Junos OS Search vendor "Juniper Networks" for product "Junos OS"				>= 22.2 < 22.2R3-S1 Search vendor "Juniper Networks" for product "Junos OS" and version " >= 22.2 < 22.2R3-S1"		en		Affected
Juniper Networks Search vendor "Juniper Networks"		Junos OS Search vendor "Juniper Networks" for product "Junos OS"				>= 22.3 < 22.3R3 Search vendor "Juniper Networks" for product "Junos OS" and version " >= 22.3 < 22.3R3"		en		Affected
Juniper Networks Search vendor "Juniper Networks"		Junos OS Search vendor "Juniper Networks" for product "Junos OS"				>= 22.4 < 22.4R3 Search vendor "Juniper Networks" for product "Junos OS" and version " >= 22.4 < 22.4R3"		en		Affected
Juniper Networks Search vendor "Juniper Networks"		Junos OS Evolved Search vendor "Juniper Networks" for product "Junos OS Evolved"				< 21.2R3-S6-EVO Search vendor "Juniper Networks" for product "Junos OS Evolved" and version " < 21.2R3-S6-EVO"		en		Affected
Juniper Networks Search vendor "Juniper Networks"		Junos OS Evolved Search vendor "Juniper Networks" for product "Junos OS Evolved"				>= 21.3-EVO < 21.3R3-S5-EVO Search vendor "Juniper Networks" for product "Junos OS Evolved" and version " >= 21.3-EVO < 21.3R3-S5-EVO"		en		Affected
Juniper Networks Search vendor "Juniper Networks"		Junos OS Evolved Search vendor "Juniper Networks" for product "Junos OS Evolved"				>= 21.4-EVO < 21.4R3-S4-EVO Search vendor "Juniper Networks" for product "Junos OS Evolved" and version " >= 21.4-EVO < 21.4R3-S4-EVO"		en		Affected
Juniper Networks Search vendor "Juniper Networks"		Junos OS Evolved Search vendor "Juniper Networks" for product "Junos OS Evolved"				>= 22.1-EVO < 22.1R3-S3-EVO Search vendor "Juniper Networks" for product "Junos OS Evolved" and version " >= 22.1-EVO < 22.1R3-S3-EVO"		en		Affected
Juniper Networks Search vendor "Juniper Networks"		Junos OS Evolved Search vendor "Juniper Networks" for product "Junos OS Evolved"				>= 22.2-EVO < 22.2R3-S1-EVO Search vendor "Juniper Networks" for product "Junos OS Evolved" and version " >= 22.2-EVO < 22.2R3-S1-EVO"		en		Affected
Juniper Networks Search vendor "Juniper Networks"		Junos OS Evolved Search vendor "Juniper Networks" for product "Junos OS Evolved"				>= 22.3-EVO < 22.3R3-EVO Search vendor "Juniper Networks" for product "Junos OS Evolved" and version " >= 22.3-EVO < 22.3R3-EVO"		en		Affected
Juniper Networks Search vendor "Juniper Networks"		Junos OS Evolved Search vendor "Juniper Networks" for product "Junos OS Evolved"				>= 22.4-EVO < 22.4R3-EVO Search vendor "Juniper Networks" for product "Junos OS Evolved" and version " >= 22.4-EVO < 22.4R3-EVO"		en		Affected