Remote rpd crash on Juniper Junos routers via BGP labeled-unicast can cause network-wide outages; Juniper gear is widely deployed in enterprises and service providers.
CVE-2026-102027
Juniper rpd buffer-size flaw lets eBGP neighbor crash routing daemon.
Is CVE-2026-102027 being exploited?
Not confirmed. CVE-2026-102027 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.46% probability of exploitation in the next 30 days.
How severe is CVE-2026-102027?
CVE-2026-102027 is rated High with a CVSS score of 8.7. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-102027?
Not known from our data. No patch reference has been recorded for CVE-2026-102027, which is not the same as no patch existing — a fix may have shipped without a tagged reference, or after this record was written. The vendor advisory is the only authority on whether a fix exists, and mitigations may be available regardless.
What does CVE-2026-102027 affect?
CVE-2026-102027 affects Juniper Junos OS, Juniper Junos OS Evolved, rpd (routing protocol daemon). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-102027?
Apply vendor patch when released; restrict/unfilter eBGP peers; disable affected multipath features; monitor rpd.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote DoS: a configured eBGP neighbor can trigger rpd crash via labeled-unicast UPDATEs when multipath is enabled, causing routing outages.
Immediate action required
- affected>= 24.4 and < 24.4R2-S5
- affected>= 25.2 and < 25.2R2-S2
- affected>= 25.4 and < 25.4R1-S3
- affected>= 26.2 and < 26.2R1-S2
- affected>= 24.4 and < 24.4R2-S5-EVO
- affected>= 25.2 and < 25.2R2-S2-EVO
- affected>= 25.4 and < 25.4R1-S3-EVO
- affected>= 26.2 and < 26.2R1-S2-EVO
- affected>= 25.2X100 and < 25.2X100-D35-EVO
- affected>= 25.4X300 and < 25.4X300-D40-EVO
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.