CVE-2021-0209: Junos OS Evolved: Receipt of certain valid BGP update packets from BGP peers may cause RPD to core when using REGEX.

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-01-15 · updated 2026-06-17
Weakness: CWE-824

Description

In Juniper Networks Junos OS Evolved an attacker sending certain valid BGP update packets may cause Junos OS Evolved to access an uninitialized pointer causing RPD to core leading to a Denial of Service (DoS). Continued receipt of these types of valid BGP update packets will cause an extended Denial of Service condition. RPD will require a restart to recover. An indicator of compromise is to see if the file rpd.re exists by issuing the command: show system core-dumps This issue affects: Juniper Networks Junos OS Evolved 19.4 versions prior to 19.4R2-S2-EVO; 20.1 versions prior to 20.1R1-S2-EVO, 20.1R2-S1-EVO. This issue does not affect Junos OS.

Affected products

Juniper Networks Junos OS Evolved: 19.4-r1, 19.4-r2, 19.4-r2-s1, 20.1, 20.1-r1, 20.1-r1-s1

References

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