CVE-2026-102078
Junos OS: SRX Series: A high volume of DNS traffic over TCP can lead to a flowd crash
Juniper Networks Junos OSNetwork & edge
CVSS
5.9MediumExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.33%Chance of exploitation activity in the next 30 days, higher than 24% of CVEs. Scored 23 Oct 2026FIRST EPSS
What fixes it
- 23.2R2-S5Junos OSCVE List
- 23.4R2-S6Junos OSCVE List
- 24.2R2-S3Junos OSCVE List
- 24.4R2-S1Junos OSCVE List
- 25.2R1-S1, 25.2R2Junos OSCVE List
A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.
Description
A Use After Free vulnerability in the packet forwarding engine (pfe) of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS).
When web filtering for TCP traffic is configured, a high volume of DNS requests increases the likelihood of a flowd crash and restart, which leads to a complete service outage until the service has automatically recovered. This is a race condition outside the attacker's direct control.
This issue affects Junos OS on SRX Series:
- All versions before 23.2R2-S5;
- from 23.4 before 23.4R2-S6;
- from 24.2 before 24.2R2-S3;
- from 24.4 before 24.4R2-S1;
- from 25.2 before 25.2R1-S1, 25.2R2.
Text from CVE List
Affected versions 5
- Junos OSaffected: all versions before 23.2R2-S5CVE List
- Junos OSaffected: 23.4 before 23.4R2-S6CVE List
- Junos OSaffected: 24.2 before 24.2R2-S3CVE List
- Junos OSaffected: 24.4 before 24.4R2-S1CVE List
- Junos OSaffected: 25.2 before 25.2R1-S1, 25.2R2CVE List