CVE-2026-33801

An Improper Check for Unusual or Exceptional Conditions vulnerability in the routing protocol daemon (RPD) of Juniper Networks Junos OS and Junos OS Evolved allows an adjacent, unauthenticated attacker sending a specific BGP update over an established BGP session to cause a Denial-of-Service (DoS). Upon receipt of a specifically malformed non-inet/inet6 unicast BGP update, an RPD crash and restart is triggered, which will cause a complete service outage until routing has reconverged. The rpd crash occurs before the update can be readvertised, so there is no downstream propagation. This issue affects: * Junos OS versions 25.2 before 25.2R2; * Junos OS Evolved versions 25.2 before 25.2R2-EVO. This issue doesn't affect Junos OS versions before 25.2R1 nor Junos OS Evolved versions before 25.2R1-EVO.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://supportportal.juniper.net/JSA110076	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:juniper:junos:25.2:-::::::
	cpe:2.3:o:juniper:junos:25.2:r1::::::
	cpe:2.3:o:juniper:junos:25.2:r1-s1::::::
	cpe:2.3:o:juniper:junos:25.2:r1-s2::::::

Configuration 2 (hide)

OR	cpe:2.3:o:juniper:junos_os_evolved:25.2:-::::::
	cpe:2.3:o:juniper:junos_os_evolved:25.2:r1::::::
	cpe:2.3:o:juniper:junos_os_evolved:25.2:r1-s1::::::
	cpe:2.3:o:juniper:junos_os_evolved:25.2:r1-s2::::::

History

No history.

Information

Published : 2026-07-09 21:16

Updated : 2026-07-13 20:36

NVD link : CVE-2026-33801

Mitre link : CVE-2026-33801

CVE.ORG link : CVE-2026-33801

JSON object : View

Products Affected

juniper

junos_os_evolved
junos

CWE

CWE-754

Improper Check for Unusual or Exceptional Conditions

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