An Uncontrolled Resource Consumption vulnerability in the handling of IPv6 neighbor state change events in Juniper Networks Junos OS allows an adjacent attacker to cause a memory leak in the Flexible PIC Concentrator (FPC) of an ACX5448 router. The continuous flapping of an IPv6 neighbor with specific timing will cause the FPC to run out of resources, leading to a Denial of Service (DoS) condition. Once the condition occurs, further packet processing will be impacted, creating a sustained Denial of Service (DoS) condition, requiring a manual PFE restart to restore service. The following error messages will be seen after the FPC resources have been exhausted: fpc0 DNX_NH::dnx_nh_tag_ipv4_hw_install(),3135: dnx_nh_tag_ipv4_hw_install: BCM L3 Egress create object failed for NH 602 (-14:No resources for operation), BCM NH Params: unit:0 Port:41, L3_INTF:0 Flags: 0x40 fpc0 DNX_NH::dnx_nh_tag_ipv4_hw_install(),3135: dnx_nh_tag_ipv4_hw_install: BCM L3 Egress create object failed for NH 602 (-14:No resources for operation), BCM NH Params: unit:0 Port:41, L3_INTF:0 Flags: 0x40 fpc0 DNX_NH::dnx_nh_tag_ipv4_hw_install(),3135: dnx_nh_tag_ipv4_hw_install: BCM L3 Egress create object failed for NH 602 (-14:No resources for operation), BCM NH Params: unit:0 Port:41, L3_INTF:0 Flags: 0x40 fpc0 DNX_NH::dnx_nh_tag_ipv4_hw_install(),3135: dnx_nh_tag_ipv4_hw_install: BCM L3 Egress create object failed for NH 602 (-14:No resources for operation), BCM NH Params: unit:0 Port:41, L3_INTF:0 Flags: 0x40 This issue only affects the ACX5448 router. No other products or platforms are affected by this vulnerability. This issue affects Juniper Networks Junos OS on ACX5448: 18.4 versions prior to 18.4R3-S10; 19.1 versions prior to 19.1R3-S5; 19.2 versions prior to 19.2R1-S8, 19.2R3-S2; 19.3 versions prior to 19.3R2-S6, 19.3R3-S2; 19.4 versions prior to 19.4R1-S3, 19.4R2-S2, 19.4R3; 20.1 versions prior to 20.1R2; 20.2 versions prior to 20.2R1-S1, 20.2R2.
| Software | From | Fixed in |
|---|---|---|
| juniper / junos | 18.4-r1 | 18.4-r1.x |
| juniper / junos | 18.4 | 18.4.x |
| juniper / junos | 18.4-r1-s1 | 18.4-r1-s1.x |
| juniper / junos | 18.4-r1-s3 | 18.4-r1-s3.x |
| juniper / junos | 18.4-r1-s4 | 18.4-r1-s4.x |
| juniper / junos | 18.4-r1-s2 | 18.4-r1-s2.x |
| juniper / junos | 18.4-r2 | 18.4-r2.x |
| juniper / junos | 18.4-r1-s5 | 18.4-r1-s5.x |
| juniper / junos | 18.4-r2-s1 | 18.4-r2-s1.x |
| juniper / junos | 18.4-r2-s2 | 18.4-r2-s2.x |
| juniper / junos | 18.4-r3 | 18.4-r3.x |
| juniper / junos | 18.4-r2-s3 | 18.4-r2-s3.x |
| juniper / junos | 18.4-r1-s6 | 18.4-r1-s6.x |
| juniper / junos | 18.4-r3-s2 | 18.4-r3-s2.x |
| juniper / junos | 18.4-r3-s1 | 18.4-r3-s1.x |
| juniper / junos | 18.4-r2-s4 | 18.4-r2-s4.x |
| juniper / junos | 18.4-r3-s3 | 18.4-r3-s3.x |
| juniper / junos | 18.4-r3-s4 | 18.4-r3-s4.x |
| juniper / junos | 18.4-r3-s5 | 18.4-r3-s5.x |
| juniper / junos | 18.4-r2-s5 | 18.4-r2-s5.x |
| juniper / junos | 18.4-r2-s6 | 18.4-r2-s6.x |
| juniper / junos | 18.4-r1-s7 | 18.4-r1-s7.x |
| juniper / junos | 18.4-r3-s6 | 18.4-r3-s6.x |
| juniper / junos | 18.4-r3-s7 | 18.4-r3-s7.x |
| juniper / junos | 18.4-r2-s7 | 18.4-r2-s7.x |
| juniper / junos | 18.4-r2-s8 | 18.4-r2-s8.x |
| juniper / junos | 18.4-r3-s8 | 18.4-r3-s8.x |
| juniper / junos | 18.4-r3-s9 | 18.4-r3-s9.x |
| juniper / junos | 19.1-r2-s3 | 19.1-r2-s3.x |
| juniper / junos | 19.1-r2-s2 | 19.1-r2-s2.x |
| juniper / junos | 19.1-r1-s6 | 19.1-r1-s6.x |
| juniper / junos | 19.1-r3-s3 | 19.1-r3-s3.x |
| juniper / junos | 19.1-r3-s4 | 19.1-r3-s4.x |
| juniper / junos | 19.1-r1-s5 | 19.1-r1-s5.x |
| juniper / junos | 19.1-r3-s2 | 19.1-r3-s2.x |
| juniper / junos | 19.1-r2 | 19.1-r2.x |
| juniper / junos | 19.1-r1-s4 | 19.1-r1-s4.x |
| juniper / junos | 19.1-r2-s1 | 19.1-r2-s1.x |
| juniper / junos | 19.1-r3 | 19.1-r3.x |
| juniper / junos | 19.1-r3-s1 | 19.1-r3-s1.x |
| juniper / junos | 19.1-r1-s1 | 19.1-r1-s1.x |
| juniper / junos | 19.1-r1-s3 | 19.1-r1-s3.x |
| juniper / junos | 19.1-r1-s2 | 19.1-r1-s2.x |
| juniper / junos | 19.1-r1 | 19.1-r1.x |
| juniper / junos | 19.1 | 19.1.x |
| juniper / junos | 19.2-r1 | 19.2-r1.x |
| juniper / junos | 19.2-r1-s1 | 19.2-r1-s1.x |
| juniper / junos | 19.2-r1-s2 | 19.2-r1-s2.x |
| juniper / junos | 19.2-r1-s3 | 19.2-r1-s3.x |
| juniper / junos | 19.2 | 19.2.x |
| juniper / junos | 19.2-r1-s4 | 19.2-r1-s4.x |
| juniper / junos | 19.2-r2 | 19.2-r2.x |
| juniper / junos | 19.2-r2-s1 | 19.2-r2-s1.x |
| juniper / junos | 19.2-r3 | 19.2-r3.x |
| juniper / junos | 19.2-r1-s5 | 19.2-r1-s5.x |
| juniper / junos | 19.2-r3-s1 | 19.2-r3-s1.x |
| juniper / junos | 19.2-r1-s6 | 19.2-r1-s6.x |
| juniper / junos | 19.2-r1-s7 | 19.2-r1-s7.x |
| juniper / junos | 19.3-r3-s1 | 19.3-r3-s1.x |
| juniper / junos | 19.3-r2-s5 | 19.3-r2-s5.x |
| juniper / junos | 19.3-r3 | 19.3-r3.x |
| juniper / junos | 19.3-r2-s4 | 19.3-r2-s4.x |
| juniper / junos | 19.3-r2-s3 | 19.3-r2-s3.x |
| juniper / junos | 19.3-r2-s2 | 19.3-r2-s2.x |
| juniper / junos | 19.3-r2 | 19.3-r2.x |
| juniper / junos | 19.3-r2-s1 | 19.3-r2-s1.x |
| juniper / junos | 19.3-r1-s1 | 19.3-r1-s1.x |
| juniper / junos | 19.3 | 19.3.x |
| juniper / junos | 19.3-r1 | 19.3-r1.x |
| juniper / junos | 19.4-r1 | 19.4-r1.x |
| juniper / junos | 19.4-r1-s2 | 19.4-r1-s2.x |
| juniper / junos | 19.4-r1-s1 | 19.4-r1-s1.x |
| juniper / junos | 19.4-r2 | 19.4-r2.x |
| juniper / junos | 19.4-r2-s1 | 19.4-r2-s1.x |
| juniper / junos | 20.1-r1 | 20.1-r1.x |
| juniper / junos | 20.1-r1-s2 | 20.1-r1-s2.x |
| juniper / junos | 20.1-r1-s3 | 20.1-r1-s3.x |
| juniper / junos | 20.1-r1-s4 | 20.1-r1-s4.x |
| juniper / junos | 20.1-r1-s1 | 20.1-r1-s1.x |
| juniper / junos | 20.2-r1 | 20.2-r1.x |
A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.
CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.
A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.
Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.
Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.
SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.