Junos OS: BGP session termination upon receipt of specific BGP FlowSpec advertisement.
Published Apr 8, 2020 · Updated Oct 23, 2026
Original summary
Normalized public record · Updated Oct 23, 2026
Junos OS: BGP session termination upon receipt of specific BGP FlowSpec advertisement.
Publisher and source text is retained separately from QFinch interpretation.
QFinch assessment
A vulnerability in the BGP FlowSpec implementation may cause a Juniper Networks Junos OS device to terminate an established BGP session upon receiving a specific BGP FlowSpec advertisement. The BGP NOTIFICATION message that terminates an established BGP session is sent toward the peer device that originally sent the specific BGP FlowSpec advertisement. This specific BGP FlowSpec advertisement received from a BGP peer might get propagated from a Junos OS device running the fixed release to another device that is vulnerable causing BGP session termination downstream. This issue affects IPv4 and IPv6 BGP FlowSpec deployment. This issue affects Juniper Networks Junos OS: 12.3; 12.3X48 on SRX Series; 14.1X53 on EX and QFX Series; 15.1 versions prior to 15.1R7-S5; 15.1F versions prior to 15.1F6-S13; 15.1X49 versions prior to 15.1X49-D180 on SRX Series; 15.1X53 versions prior to 15.1X53-D238 on QFX5200/QFX5110; 15.1X53 versions prior to 15.1X53-D497 on NFX Series; 15.1X53 versions prior to 15.1X53-D592 on EX2300/EX3400; 16.1 versions prior to 16.1R7-S7; 17.1 versions prior to 17.1R2-S12, 17.1R3; 17.2 versions prior to 17.2R2-S7, 17.2R3; 17.2X75 versions prior to 17.2X75-D102, 17.2X75-D110, 17.2X75-D44; 17.3 versions prior to 17.3R2-S5, 17.3R3-S5; 17.4 versions prior to 17.4R1-S8, 17.4R2; 18.1 versions prior to 18.1R2-S4, 18.1R3; 18.2X75 versions prior to 18.2X75-D20.
Evidence: public source recordsAffected products
| Affected package, product or range | Fix status |
|---|---|
| Consult the referenced vendor advisory for affected versions. | Consult source advisory |
Matching a version is only one part of assessing exposure. QFinch has not assessed your environment on this public page.
Remediation
Apply the vendor-supported fixed release or mitigation, then verify the affected component is no longer reachable.
- Confirm the affected product and reachable code path exist in your environment.
- Apply the vendor-supported patch or mitigation from the primary advisory.
- Rescan the exact deployed revision and retain verification evidence.
Evidence coverage
- SSVC priority
- MEDIUM
- Confidence
- 10%
- Aliases
- None reported
Scores appear only when corresponding evidence exists. Missing data is never interpreted as zero risk.
Sources and record history
Record history
Published Apr 8, 2020 · Last refreshed Oct 23, 2026