High 7.6Published Oct 14, 2026

CVE-2026-102177Junos OS and Junos OS Evolved: An out-of-bounds write causes an rpd crash when IS-IS backup selection is used

Updated under an hour ago (Oct 27, 2026, 11:10 PM ET)

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It affects Juniper Networks Junos OS and 1 other product. Add what you run to find out whether that includes you.

EPSS puts the chance of exploitation in the next 30 days at 0.27%, higher than 19% of scored CVEs.

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Every CVE for Juniper Networks Junos OS

Exploited in the last 30 days

An Out-of-bounds Write vulnerability in the routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows an adjacent unauthenticated attacker to cause a denial of service when IS-IS link protection and backup-selection are configured.

CVSS: 7.6 HIGH (v3.1, CNA)CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H
Weakness (CWE): CWE-787
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): 0.27% (percentile 19)
Assigned by: juniper
NVD analysis: Awaiting Analysis
Record last updated: Oct 14, 2026
First seen by InfoSec Signals: Oct 14, 2026

Affected products

Affected products

Juniper Networks Junos OS juniper_networks:junos_os (from the name)	before 23.2R2-S7.7; from 23.4 before 23.4R2-S8.13; from 24.2 before 24.2R2-S5.5; from 24.4 before 24.4R2-S5; from 25.2 before 25.2R2-S2; from 25.4 before 25.4R1-S3; from 26.2 before 26.2R1-S2	CNA record
Juniper Networks Junos OS Evolved juniper_networks:junos_os_evolved (from the name)	before 23.2R2-S7.7-EVO; from 23.4 before 23.4R2-S8.11-EVO; from 24.2 before 24.2R2-S5.6-EVO; from 24.4 before 24.4R2-S5-EVO; from 25.2 before 25.2R2-S2-EVO; from 25.4 before 25.4R1-S3-EVO; from 26.2 before 26.2R1-S2-EVO; 23.4X100; and 2 more ranges	CNA record

References

References

https://supportportal.juniper.net/JSA112187	vendor-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.