Insufficient Cross-Site Scripting (XSS) protection in J-Web may potentially allow a remote attacker to inject web script or HTML, hijack the target user's J-Web session and perform administrative actions on the Junos device as the targeted user. This issue affects Juniper Networks Junos OS 12.3 versions prior to 12.3R12-S15; 12.3X48 versions prior to 12.3X48-D86, 12.3X48-D90 on SRX Series; 14.1X53 versions prior to 14.1X53-D51 on EX and QFX Series; 15.1F6 versions prior to 15.1F6-S13; 15.1 versions prior to 15.1R7-S5; 15.1X49 versions prior to 15.1X49-D181, 15.1X49-D190 on SRX Series; 15.1X53 versions prior to 15.1X53-D238 on QFX5200/QFX5110 Series; 15.1X53 versions prior to 15.1X53-D592 on EX2300/EX3400 Series; 16.1 versions prior to 16.1R4-S13, 16.1R7-S5; 16.2 versions prior to 16.2R2-S10; 17.1 versions prior to 17.1R2-S11, 17.1R3-S1; 17.2 versions prior to 17.2R1-S9, 17.2R3-S2; 17.3 versions prior to 17.3R2-S5, 17.3R3-S5; 17.4 versions prior to 17.4R2-S6, 17.4R3; 18.1 versions prior to 18.1R3-S7; 18.2 versions prior to 18.2R2-S5, 18.2R3; 18.3 versions prior to 18.3R1-S6, 18.3R2-S1, 18.3R3; 18.4 versions prior to 18.4R1-S5, 18.4R2; 19.1 versions prior to 19.1R1-S2, 19.1R2.
| Software | From | Fixed in |
|---|---|---|
| juniper / junos | 17.1-r3 | 17.1-r3.x |
| juniper / junos | 12.3-r11 | 12.3-r11.x |
| juniper / junos | 12.3-r2 | 12.3-r2.x |
| juniper / junos | 12.3-r9 | 12.3-r9.x |
| juniper / junos | 16.1-r1 | 16.1-r1.x |
| juniper / junos | 15.1-r3 | 15.1-r3.x |
| juniper / junos | 12.3-r4 | 12.3-r4.x |
| juniper / junos | 16.2-r2 | 16.2-r2.x |
| juniper / junos | 12.3-r1 | 12.3-r1.x |
| juniper / junos | 15.1-r6 | 15.1-r6.x |
| juniper / junos | 15.1-r4 | 15.1-r4.x |
| juniper / junos | 12.3-r7 | 12.3-r7.x |
| juniper / junos | 12.3-r6 | 12.3-r6.x |
| juniper / junos | 15.1-f6 | 15.1-f6.x |
| juniper / junos | 12.3-r12 | 12.3-r12.x |
| juniper / junos | 15.1-r2 | 15.1-r2.x |
| juniper / junos | 16.1-r4 | 16.1-r4.x |
| juniper / junos | 17.1-r1 | 17.1-r1.x |
| juniper / junos | 16.2-r1 | 16.2-r1.x |
| juniper / junos | 12.3-r13 | 12.3-r13.x |
| juniper / junos | 16.1-r4-s3 | 16.1-r4-s3.x |
| juniper / junos | 12.3-r5 | 12.3-r5.x |
| juniper / junos | 15.1-r5 | 15.1-r5.x |
| juniper / junos | 12.3-r3 | 12.3-r3.x |
| juniper / junos | 15.1-r1 | 15.1-r1.x |
| juniper / junos | 16.1-r3 | 16.1-r3.x |
| juniper / junos | 12.3-r8 | 12.3-r8.x |
| juniper / junos | 16.1-r2 | 16.1-r2.x |
| juniper / junos | 17.2-r1-s2 | 17.2-r1-s2.x |
| juniper / junos | 15.1-r4-s9 | 15.1-r4-s9.x |
| juniper / junos | 15.1-r6-s6 | 15.1-r6-s6.x |
| juniper / junos | 16.1-r5-s4 | 16.1-r5-s4.x |
| juniper / junos | 16.1-r6-s1 | 16.1-r6-s1.x |
| juniper / junos | 16.1-r7 | 16.1-r7.x |
| juniper / junos | 16.2-r2-s5 | 16.2-r2-s5.x |
| juniper / junos | 17.1-r2-s7 | 17.1-r2-s7.x |
| juniper / junos | 17.3-r2 | 17.3-r2.x |
| juniper / junos | 17.4-r1 | 17.4-r1.x |
| juniper / junos | 17.4-r2 | 17.4-r2.x |
| juniper / junos | 16.1-r4-s9 | 16.1-r4-s9.x |
| juniper / junos | 17.3-r2-s2 | 17.3-r2-s2.x |
| juniper / junos | 15.1-f6-s3 | 15.1-f6-s3.x |
| juniper / junos | 18.1-r3 | 18.1-r3.x |
| juniper / junos | 15.1-r7-s1 | 15.1-r7-s1.x |
| juniper / junos | 17.2-r2-s6 | 17.2-r2-s6.x |
| juniper / junos | 12.3-r12-s10 | 12.3-r12-s10.x |
| juniper / junos | 18.1-r2 | 18.1-r2.x |
| juniper / junos | 16.1-r3-s10 | 16.1-r3-s10.x |
| juniper / junos | 17.2-r1-s7 | 17.2-r1-s7.x |
| juniper / junos | 15.1-r7-s2 | 15.1-r7-s2.x |
| juniper / junos | 15.1-r7-s3 | 15.1-r7-s3.x |
| juniper / junos | 17.4-r1-s1 | 17.4-r1-s1.x |
| juniper / junos | 18.2 | 18.2.x |
| juniper / junos | 18.2-r2-s1 | 18.2-r2-s1.x |
| juniper / junos | 18.2-r2-s2 | 18.2-r2-s2.x |
| juniper / junos | 18.3-r1-s1 | 18.3-r1-s1.x |
| juniper / junos | 17.2-r1-s4 | 17.2-r1-s4.x |
| juniper / junos | 17.3-r3-s1 | 17.3-r3-s1.x |
| juniper / junos | 17.3-r3-s2 | 17.3-r3-s2.x |
| juniper / junos | 17.4-r1-s2 | 17.4-r1-s2.x |
| juniper / junos | 17.3-r2-s1 | 17.3-r2-s1.x |
| juniper / junos | 18.3-r2 | 18.3-r2.x |
| juniper / junos | 18.3-r1 | 18.3-r1.x |
| juniper / junos | 17.4-r2-s1 | 17.4-r2-s1.x |
| juniper / junos | 16.2-r2-s1 | 16.2-r2-s1.x |
| juniper / junos | 16.2-r2-s2 | 16.2-r2-s2.x |
| juniper / junos | 16.2-r2-s6 | 16.2-r2-s6.x |
| juniper / junos | 16.2-r2-s7 | 16.2-r2-s7.x |
| juniper / junos | 16.2-r2-s8 | 16.2-r2-s8.x |
| juniper / junos | 17.1-r2-s1 | 17.1-r2-s1.x |
| juniper / junos | 17.1-r2-s2 | 17.1-r2-s2.x |
| juniper / junos | 17.1-r2-s3 | 17.1-r2-s3.x |
| juniper / junos | 17.1-r2-s4 | 17.1-r2-s4.x |
| juniper / junos | 17.1-r2-s5 | 17.1-r2-s5.x |
| juniper / junos | 17.1-r2-s6 | 17.1-r2-s6.x |
| juniper / junos | 18.1-r2-s2 | 18.1-r2-s2.x |
| juniper / junos | 15.1-f6-s1 | 15.1-f6-s1.x |
| juniper / junos | 18.4-r1 | 18.4-r1.x |
| juniper / junos | 17.4 | 17.4.x |
| juniper / junos | 18.1-r3-s4 | 18.1-r3-s4.x |
| juniper / junos | 18.1-r3-s3 | 18.1-r3-s3.x |
| juniper / junos | 18.1-r3-s2 | 18.1-r3-s2.x |
| juniper / junos | 18.1 | 18.1.x |
| juniper / junos | 18.1-r2-s1 | 18.1-r2-s1.x |
| juniper / junos | 18.1-r2-s4 | 18.1-r2-s4.x |
| juniper / junos | 16.1 | 16.1.x |
| juniper / junos | 16.2 | 16.2.x |
| juniper / junos | 17.1 | 17.1.x |
| juniper / junos | 17.2 | 17.2.x |
| juniper / junos | 17.3 | 17.3.x |
| juniper / junos | 18.3-r1-s2 | 18.3-r1-s2.x |
| juniper / junos | 18.3 | 18.3.x |
| juniper / junos | 18.4 | 18.4.x |
| juniper / junos | 18.1-r3-s1 | 18.1-r3-s1.x |
| juniper / junos | 17.3-r3-s3 | 17.3-r3-s3.x |
| juniper / junos | 17.1-r2-s10 | 17.1-r2-s10.x |
| juniper / junos | 17.4-r1-s7 | 17.4-r1-s7.x |
| juniper / junos | 12.3 | 12.3.x |
| juniper / junos | 17.4-r1-s4 | 17.4-r1-s4.x |
| juniper / junos | 18.4-r1-s1 | 18.4-r1-s1.x |
| juniper / junos | 17.3-r3-s4 | 17.3-r3-s4.x |
| juniper / junos | 17.4-r2-s3 | 17.4-r2-s3.x |
| juniper / junos | 17.4-r2-s4 | 17.4-r2-s4.x |
| juniper / junos | 17.4-r1-s6 | 17.4-r1-s6.x |
| juniper / junos | 18.1-r3-s5 | 18.1-r3-s5.x |
| juniper / junos | 18.3-r1-s3 | 18.3-r1-s3.x |
| juniper / junos | 17.2-r2-s7 | 17.2-r2-s7.x |
| juniper / junos | 18.2-r2-s3 | 18.2-r2-s3.x |
| juniper / junos | 18.2-r2-s4 | 18.2-r2-s4.x |
| juniper / junos | 18.3-r1-s4 | 18.3-r1-s4.x |
| juniper / junos | 18.2-r1-s5 | 18.2-r1-s5.x |
| juniper / junos | 17.2-r1-s8 | 17.2-r1-s8.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 | 19.1-r1 | 19.1-r1.x |
| juniper / junos | 16.2-r2-s9 | 16.2-r2-s9.x |
| juniper / junos | 16.1-r7-s3 | 16.1-r7-s3.x |
| juniper / junos | 16.1-r7-s4 | 16.1-r7-s4.x |
| juniper / junos | 17.4-r2-s5 | 17.4-r2-s5.x |
| juniper / junos | 18.1-r3-s6 | 18.1-r3-s6.x |
| juniper / junos | 19.1-r1-s1 | 19.1-r1-s1.x |
| juniper / junos | 12.3-r12-s13 | 12.3-r12-s13.x |
| juniper / junos | 12.3-r12-s14 | 12.3-r12-s14.x |
| juniper / junos | 15.1-r7-s4 | 15.1-r7-s4.x |
| juniper / junos | 17.3-r1-s1 | 17.3-r1-s1.x |
| juniper / junos | 16.1-r7-s2 | 16.1-r7-s2.x |
| juniper / junos | 15.1-f6-s12 | 15.1-f6-s12.x |
| juniper / junos | 18.3-r1-s5 | 18.3-r1-s5.x |
| juniper / junos | 12.3-r12-s1 | 12.3-r12-s1.x |
| juniper / junos | 12.3-r12-s3 | 12.3-r12-s3.x |
| juniper / junos | 12.3-r12-s4 | 12.3-r12-s4.x |
| juniper / junos | 12.3-r12-s6 | 12.3-r12-s6.x |
| juniper / junos | 12.3-r12-s11 | 12.3-r12-s11.x |
| juniper / junos | 12.3-r12-s12 | 12.3-r12-s12.x |
| juniper / junos | 16.1-r4-s12 | 16.1-r4-s12.x |
| juniper / junos | 16.1-r4-s6 | 16.1-r4-s6.x |
| juniper / junos | 16.1-r4-s2 | 16.1-r4-s2.x |
| juniper / junos | 17.3-r2-s4 | 17.3-r2-s4.x |
| juniper / junos | 12.3x48-d15 | 12.3x48-d15.x |
| juniper / junos | 12.3x48-d25 | 12.3x48-d25.x |
| juniper / junos | 12.3x48-d80 | 12.3x48-d80.x |
| juniper / junos | 12.3x48-d10 | 12.3x48-d10.x |
| juniper / junos | 15.1x49-d60 | 15.1x49-d60.x |
| juniper / junos | 15.1x49-d150 | 15.1x49-d150.x |
| juniper / junos | 15.1x49-d180 | 15.1x49-d180.x |
| juniper / junos | 15.1x49-d170 | 15.1x49-d170.x |
| juniper / junos | 15.1x49-d40 | 15.1x49-d40.x |
| juniper / junos | 15.1x49-d20 | 15.1x49-d20.x |
| juniper / junos | 15.1x49-d10 | 15.1x49-d10.x |
| juniper / junos | 15.1x49-d55 | 15.1x49-d55.x |
| juniper / junos | 15.1x49-d35 | 15.1x49-d35.x |
| juniper / junos | 15.1x49-d45 | 15.1x49-d45.x |
| juniper / junos | 15.1x49-d75 | 15.1x49-d75.x |
| juniper / junos | 15.1x49-d65 | 15.1x49-d65.x |
| juniper / junos | 15.1x49-d90 | 15.1x49-d90.x |
| juniper / junos | 15.1x49-d50 | 15.1x49-d50.x |
| juniper / junos | 15.1x49-d30 | 15.1x49-d30.x |
| juniper / junos | 15.1x49-d70 | 15.1x49-d70.x |
| juniper / junos | 15.1x49-d80 | 15.1x49-d80.x |
| juniper / junos | 14.1x53-d45 | 14.1x53-d45.x |
| juniper / junos | 14.1x53-d15 | 14.1x53-d15.x |
| juniper / junos | 14.1x53-d35 | 14.1x53-d35.x |
| juniper / junos | 14.1x53-d10 | 14.1x53-d10.x |
| juniper / junos | 14.1x53-d40 | 14.1x53-d40.x |
| juniper / junos | 14.1x53-d30 | 14.1x53-d30.x |
| juniper / junos | 14.1x53-d25 | 14.1x53-d25.x |
| juniper / junos | 14.1x53-d27 | 14.1x53-d27.x |
| juniper / junos | 14.1x53-d16 | 14.1x53-d16.x |
| juniper / junos | 14.1x53-d26 | 14.1x53-d26.x |
| juniper / junos | 14.1x53-d46 | 14.1x53-d46.x |
| juniper / junos | 14.1x53-d47 | 14.1x53-d47.x |
| juniper / junos | 14.1x53-d48 | 14.1x53-d48.x |
| juniper / junos | 14.1x53 | 14.1x53.x |
| juniper / junos | 14.1x53-d49 | 14.1x53-d49.x |
| juniper / junos | 15.1x53-d40 | 15.1x53-d40.x |
| juniper / junos | 15.1x53-d62 | 15.1x53-d62.x |
| juniper / junos | 15.1x53-d20 | 15.1x53-d20.x |
| juniper / junos | 15.1x53-d30 | 15.1x53-d30.x |
| juniper / junos | 15.1x53-d33 | 15.1x53-d33.x |
| juniper / junos | 15.1x53-d25 | 15.1x53-d25.x |
| juniper / junos | 15.1x53-d63 | 15.1x53-d63.x |
| juniper / junos | 15.1x53-d32 | 15.1x53-d32.x |
| juniper / junos | 15.1x53-d34 | 15.1x53-d34.x |
| juniper / junos | 15.1x53-d210 | 15.1x53-d210.x |
| juniper / junos | 15.1x53-d70 | 15.1x53-d70.x |
| juniper / junos | 15.1x53-d21 | 15.1x53-d21.x |
| juniper / junos | 15.1x53-d60 | 15.1x53-d60.x |
| juniper / junos | 15.1x53-d45 | 15.1x53-d45.x |
| juniper / junos | 15.1x53-d61 | 15.1x53-d61.x |
| juniper / junos | 15.1x53-d230 | 15.1x53-d230.x |
| juniper / junos | 15.1x53-d65 | 15.1x53-d65.x |
| juniper / junos | 15.1x53-d231 | 15.1x53-d231.x |
| juniper / junos | 15.1x53-d232 | 15.1x53-d232.x |
| juniper / junos | 15.1x53-d233 | 15.1x53-d233.x |
| juniper / junos | 15.1x53-d56 | 15.1x53-d56.x |
| juniper / junos | 15.1x53-d31 | 15.1x53-d31.x |
| juniper / junos | 15.1x53-d234 | 15.1x53-d234.x |
| juniper / junos | 15.1x53-d237 | 15.1x53-d237.x |
| juniper / junos | 15.1x53-d236 | 15.1x53-d236.x |
| juniper / junos | 15.1x53-d235 | 15.1x53-d235.x |
| juniper / junos | 15.1x53-d470 | 15.1x53-d470.x |
| juniper / junos | 15.1x53-d495 | 15.1x53-d495.x |
| juniper / junos | 15.1x53-d590 | 15.1x53-d590.x |
| juniper / junos | 15.1x53-d591 | 15.1x53-d591.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.