What’s Vulnerable › Vulnerabilities
CVE-2026-102078: Junos OS: SRX Series: A high volume of DNS traffic over TCP can lead to a flowd crash
- Severity: medium (CVSS 5.9 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.3% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-10-14 · updated 2026-10-15
- Weakness: CWE-416
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.
Affected products
- Juniper Junos OS: 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 — fixed in 25.2R2, 23.2R2-S5, 23.4R2-S6, 24.2R2-S3, 24.4R2-S1, 25.2R1-S1
How to fix
Upgrade to a fixed version: Juniper Junos OS 25.2R2, 23.2R2-S5, 23.4R2-S6, 24.2R2-S3. Check the vendor advisory for mitigations.
References
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