Medium severity · published Jul 9, 2026
CVE-2026-33801
Junos OS and Junos OS Evolved: When a specifically malformed BGP route update is received RPD crashes
6.5
CVSS
0.3%
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Adjacent
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 20% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
JO
Junos OS · Juniper
25.2 before 25.2R2 · source: vendor, NVD
JO
Junos OS Evolved · Juniper Networks
25.2 before 25.2R2-EVO · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-33801
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-33801
Vendor Advisory
https://supportportal.juniper.net/JSA110076
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