Vulnerability Database

346,508

Total vulnerabilities in the database

CVE-2019-1757 — cisco / ios_xe

Improper Certificate Validation

A vulnerability in the Cisco Smart Call Home feature of Cisco IOS and IOS XE Software could allow an unauthenticated, remote attacker to gain unauthorized read access to sensitive data using an invalid certificate. The vulnerability is due to insufficient certificate validation by the affected software. An attacker could exploit this vulnerability by supplying a crafted certificate to an affected device. A successful exploit could allow the attacker to conduct man-in-the-middle attacks to decrypt confidential information on user connections to the affected software.

  • Published: Mar 28, 2019
  • Updated: Nov 9, 2025
  • CVE: CVE-2019-1757
  • Severity: Medium
  • Exploit:

CVSS v3:

  • Severity: Medium
  • Score: 5.9
  • AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

CVSS v2:

  • Severity: Low
  • Score: 4.3
  • AV:N/AC:M/Au:N/C:P/I:N/A:N
Software From Fixed in
cisco / ios_xe 3.6.5be 3.6.5be.x
cisco / ios 15.2(2)e5b 15.2(2)e5b.x
cisco / ios 12.4(25e)jap26 12.4(25e)jap26.x
cisco / ios 15.6(2)sp2 15.6(2)sp2.x
cisco / ios_xe 3.7.4e 3.7.4e.x
cisco / ios 15.6(2)t3 15.6(2)t3.x
cisco / ios_xe 3.9.0e 3.9.0e.x
cisco / ios 15.6(1)t2 15.6(1)t2.x
cisco / ios 15.5(3)s1a 15.5(3)s1a.x
cisco / ios_xe 16.2.1 16.2.1.x
cisco / ios_xe 3.8.3e 3.8.3e.x
cisco / ios 15.2(3)e4 15.2(3)e4.x
cisco / ios_xe 3.6.5ae 3.6.5ae.x
cisco / ios_xe 3.18.2s 3.18.2s.x
cisco / ios_xe 3.6.4e 3.6.4e.x
cisco / ios_xe 3.6.6e 3.6.6e.x
cisco / ios 15.6(2)t1 15.6(2)t1.x
cisco / ios 15.6(2)sp 15.6(2)sp.x
cisco / ios_xe 3.17.3s 3.17.3s.x
cisco / ios 15.2(4m)e3 15.2(4m)e3.x
cisco / ios 15.2(2)e6 15.2(2)e6.x
cisco / ios 15.6(3)m1 15.6(3)m1.x
cisco / ios_xe 3.16.4s 3.16.4s.x
cisco / ios 15.6(3)m3 15.6(3)m3.x
cisco / ios 12.4(25e)jap2 12.4(25e)jap2.x
cisco / ios_xe 3.17.1as 3.17.1as.x
cisco / ios 15.6(1)s2 15.6(1)s2.x
cisco / ios 15.5(3)s5 15.5(3)s5.x
cisco / ios_xe 3.18.2asp 3.18.2asp.x
cisco / ios 15.2(3)e5 15.2(3)e5.x
cisco / ios_xe 3.18.3s 3.18.3s.x
cisco / ios 15.2(5a)e1 15.2(5a)e1.x
cisco / ios_xe 3.18.0as 3.18.0as.x
cisco / ios 15.7(3)m 15.7(3)m.x
cisco / ios_xe 3.8.4e 3.8.4e.x
cisco / ios 15.2(4n)e2 15.2(4n)e2.x
cisco / ios 15.6(3)m2a 15.6(3)m2a.x
cisco / ios_xe 3.16.2s 3.16.2s.x
cisco / ios_xe 3.6.7e 3.6.7e.x
cisco / ios 12.4(25e)jaz1 12.4(25e)jaz1.x
cisco / ios 15.6(2)s 15.6(2)s.x
cisco / ios 15.6(2)s2 15.6(2)s2.x
cisco / ios 15.5(3)s4 15.5(3)s4.x
cisco / ios 15.3(3)ja1n 15.3(3)ja1n.x
cisco / ios_xe 3.18.3sp 3.18.3sp.x
cisco / ios_xe 16.6.1 16.6.1.x
cisco / ios_xe 3.18.1sp 3.18.1sp.x
cisco / ios_xe 3.17.4s 3.17.4s.x
cisco / ios 15.6(1)s4 15.6(1)s4.x
cisco / ios 15.6(2)t2 15.6(2)t2.x
cisco / ios 15.6(2)sn 15.6(2)sn.x
cisco / ios 15.2(5)ea 15.2(5)ea.x
cisco / ios_xe 3.16.6s 3.16.6s.x
cisco / ios 15.2(4)e2 15.2(4)e2.x
cisco / ios_xe 3.16.5s 3.16.5s.x
cisco / ios 15.5(3)s2 15.5(3)s2.x
cisco / ios 15.2(5c)e 15.2(5c)e.x
cisco / ios_xe 3.16.1s 3.16.1s.x
cisco / ios 15.6(2)s4 15.6(2)s4.x
cisco / ios_xe 3.7.5e 3.7.5e.x
cisco / ios 15.5(3)s1 15.5(3)s1.x
cisco / ios 15.2(2)e4 15.2(2)e4.x
cisco / ios 15.2(5)e2 15.2(5)e2.x
cisco / ios 15.2(4p)e1 15.2(4p)e1.x
cisco / ios 15.6(1)t1 15.6(1)t1.x
cisco / ios 15.6(3)m1b 15.6(3)m1b.x
cisco / ios_xe 3.18.1bsp 3.18.1bsp.x
cisco / ios_xe 3.8.2e 3.8.2e.x
cisco / ios_xe 3.18.1csp 3.18.1csp.x
cisco / ios_xe 3.18.0s 3.18.0s.x
cisco / ios 15.2(5b)e 15.2(5b)e.x
cisco / ios 15.2(4)e4 15.2(4)e4.x
cisco / ios 15.2(2)e5 15.2(2)e5.x
cisco / ios 15.6(3)m 15.6(3)m.x
cisco / ios 15.6(1)s3 15.6(1)s3.x
cisco / ios 15.3(3)jn2 15.3(3)jn2.x
cisco / ios_xe 3.17.0s 3.17.0s.x
cisco / ios_xe 3.16.4ds 3.16.4ds.x
cisco / ios 15.6(1)s1 15.6(1)s1.x
cisco / ios 15.6(2)t 15.6(2)t.x
cisco / ios 15.6(3)m0a 15.6(3)m0a.x
cisco / ios 15.6(2)s3 15.6(2)s3.x
cisco / ios 15.6(1)t0a 15.6(1)t0a.x
cisco / ios_xe 3.16.3s 3.16.3s.x
cisco / ios 15.2(2)e5a 15.2(2)e5a.x
cisco / ios 15.2(4)jaz1 15.2(4)jaz1.x
cisco / ios 15.6(2)sp1 15.6(2)sp1.x
cisco / ios 12.4(25e)jap1m 12.4(25e)jap1m.x
cisco / ios_xe 3.17.1s 3.17.1s.x
cisco / ios_xe 3.18.2sp 3.18.2sp.x
cisco / ios 15.6(1)s 15.6(1)s.x
cisco / ios_xe 16.4.1 16.4.1.x
cisco / ios 15.6(2)sp3 15.6(2)sp3.x
cisco / ios_xe 3.16.2bs 3.16.2bs.x
cisco / ios_xe 3.16.1as 3.16.1as.x
cisco / ios_xe 3.18.1s 3.18.1s.x
cisco / ios 15.2(5)ex 15.2(5)ex.x
cisco / ios_xe 16.2.2 16.2.2.x
cisco / ios 15.6(2)s1 15.6(2)s1.x
cisco / ios 15.6(3)m2 15.6(3)m2.x
cisco / ios_xe 3.18.0sp 3.18.0sp.x
cisco / ios_xe 3.16.3as 3.16.3as.x
cisco / ios 15.2(4o)e2 15.2(4o)e2.x
cisco / ios 15.2(4)e3 15.2(4)e3.x
cisco / ios_xe 3.16.4as 3.16.4as.x
cisco / ios 15.2(5a)e 15.2(5a)e.x
cisco / ios_xe 3.16.4bs 3.16.4bs.x
cisco / ios 15.5(3)s3 15.5(3)s3.x
cisco / ios_xe 3.6.5e 3.6.5e.x
cisco / ios 15.2(2)e7 15.2(2)e7.x
cisco / ios 15.3(3)jn1 15.3(3)jn1.x
cisco / ios_xe 16.3.1 16.3.1.x
cisco / ios 15.2(5)e1 15.2(5)e1.x
cisco / ios 15.2(5)e 15.2(5)e.x
cisco / ios_xe 3.16.2as 3.16.2as.x
cisco / ios_xe 3.18.1asp 3.18.1asp.x
cisco / ios_xe 3.9.1e 3.9.1e.x
cisco / ios 15.2(4)jn1 15.2(4)jn1.x
cisco / ios 15.6(1)t 15.6(1)t.x
cisco / ios_xe 16.3.1a 16.3.1a.x
cisco / ios_xe 16.3.2 16.3.2.x
cisco / ios_xe 16.3.3 16.3.3.x
cisco / ios 15.6(1)t3 15.6(1)t3.x
cisco / ios 15.2(5)e2b 15.2(5)e2b.x
cisco / ios_xe 3.16.6bs 3.16.6bs.x
cisco / ios_xe 16.5.1 16.5.1.x
cisco / ios_xe 16.5.1a 16.5.1a.x
cisco / ios_xe 16.3.4 16.3.4.x
cisco / ios 15.2(5)e2c 15.2(5)e2c.x
cisco / ios_xe 3.9.2e 3.9.2e.x
cisco / ios_xe 16.5.1b 16.5.1b.x
cisco / ios_xe 16.4.2 16.4.2.x
cisco / ios_xe 16.3.5b 16.3.5b.x
cisco / ios_xe 16.3.6 16.3.6.x
cisco / ios_xe 16.6.3 16.6.3.x
cisco / ios 15.6(3)m1a 15.6(3)m1a.x
cisco / ios 15.6(3)m3a 15.6(3)m3a.x
cisco / ios 15.7(3)m0a 15.7(3)m0a.x
cisco / ios 15.7(3)m1 15.7(3)m1.x
cisco / ios 15.7(3)m2 15.7(3)m2.x
cisco / ios_xe 16.8.1 16.8.1.x
cisco / ios_xe 16.7.1 16.7.1.x
cisco / ios_xe 16.6.2 16.6.2.x
cisco / ios_xe 3.8.5e 3.8.5e.x
cisco / ios 15.6(1)sn2 15.6(1)sn2.x
cisco / ios 15.1(3)svo2 15.1(3)svo2.x
cisco / ios_xe 3.16.4gs 3.16.4gs.x
cisco / ios 15.5(3)s6a 15.5(3)s6a.x
cisco / ios_xe 3.16.4cs 3.16.4cs.x
cisco / ios 15.5(3)s6b 15.5(3)s6b.x
cisco / ios 15.2(4s)e1 15.2(4s)e1.x
cisco / ios 15.2(4s)e2 15.2(4s)e2.x
cisco / ios 15.6(1)sn1 15.6(1)sn1.x
cisco / ios_xe 3.16.5bs 3.16.5bs.x
cisco / ios 15.6(1)sn3 15.6(1)sn3.x
cisco / ios_xe 3.16.4es 3.16.4es.x
cisco / ios 15.6(6)sn 15.6(6)sn.x
cisco / ios_xe 16.3.5 16.3.5.x
cisco / ios 15.2(4m)e2 15.2(4m)e2.x
cisco / ios 12.2(6)i1 12.2(6)i1.x
cisco / ios_xe 16.5.2 16.5.2.x
cisco / ios_xe 3.9.2be 3.9.2be.x
cisco / ios 15.6(1)sn 15.6(1)sn.x
cisco / ios_xe 3.16.5as 3.16.5as.x
cisco / ios 15.6(5)sn 15.6(5)sn.x
cisco / ios 15.6(7)sn 15.6(7)sn.x
cisco / ios 15.2(4)e5a 15.2(4)e5a.x
cisco / ios_xe 3.8.5ae 3.8.5ae.x
cisco / ios 15.1(3)svp1 15.1(3)svp1.x
cisco / ios 15.6(2)sp3b 15.6(2)sp3b.x
cisco / ios 15.2(3)ea1 15.2(3)ea1.x
cisco / ios 15.2(4q)e1 15.2(4q)e1.x
cisco / ios 15.6(4)sn 15.6(4)sn.x
cisco / ios 15.2(4a)ea5 15.2(4a)ea5.x
cisco / ios 15.6(3)sn 15.6(3)sn.x
cisco / ios 15.1(2)sg8a 15.1(2)sg8a.x
cisco / ios 15.5(3)s6 15.5(3)s6.x
cisco / ios 15.2(4)e5 15.2(4)e5.x
cisco / ios 15.1(4)m12c 15.1(4)m12c.x
cisco / ios 15.2(4o)e3 15.2(4o)e3.x
cisco / ios_xe 16.8.1a 16.8.1a.x
cisco / ios_xe 16.8.1s 16.8.1s.x
cisco / ios_xe 16.8.1b 16.8.1b.x
cisco / ios_xe 16.8.2 16.8.2.x
cisco / ios_xe 16.7.2 16.7.2.x
cisco / ios_xe 16.8.1d 16.8.1d.x
cisco / ios_xe 16.7.1a 16.7.1a.x
cisco / ios_xe 16.7.1b 16.7.1b.x
cisco / ios_xe 16.8.1c 16.8.1c.x
cisco / ios 15.2(4)ea9 15.2(4)ea9.x
cisco / ios 15.6(2)sp4 15.6(2)sp4.x
cisco / ios_xe 16.4.3 16.4.3.x
cisco / ios 15.6(2)t0a 15.6(2)t0a.x
cisco / ios 15.6(3)m4 15.6(3)m4.x
cisco / ios_xe 3.6.8e 3.6.8e.x
cisco / ios 15.3(3)ji 15.3(3)ji.x
cisco / ios_xe 3.10.0ce 3.10.0ce.x
cisco / ios 15.1(3)svg3d 15.1(3)svg3d.x
cisco / ios_xe 3.6.7ae 3.6.7ae.x
cisco / ios 15.2(4)e6 15.2(4)e6.x
cisco / ios_xe 3.18.3asp 3.18.3asp.x
cisco / ios 15.2(2)e7b 15.2(2)e7b.x
cisco / ios_xe 3.10.0e 3.10.0e.x
cisco / ios 15.2(6)e1 15.2(6)e1.x
cisco / ios 15.2(6)e 15.2(6)e.x
cisco / ios 15.2(4)ea8 15.2(4)ea8.x
cisco / ios 15.2(6)e0c 15.2(6)e0c.x
cisco / ios_xe 3.18.1isp 3.18.1isp.x
cisco / ios 15.1(3)svn2 15.1(3)svn2.x
cisco / ios_xe 16.9.1s 16.9.1s.x
cisco / ios 15.1(3)svi1b 15.1(3)svi1b.x
cisco / ios 15.3(3)jd15 15.3(3)jd15.x
cisco / ios_xe 3.16.7as 3.16.7as.x
cisco / ios_xe 3.18.1gsp 3.18.1gsp.x
cisco / ios 15.3(3)jf35 15.3(3)jf35.x
cisco / ios_xe 3.18.4s 3.18.4s.x
cisco / ios_xe 3.16.7s 3.16.7s.x
cisco / ios 15.1(3)svo1 15.1(3)svo1.x
cisco / ios_xe 16.9.1c 16.9.1c.x
cisco / ios_xe 3.18.3bsp 3.18.3bsp.x
cisco / ios_xe 16.9.1b 16.9.1b.x
cisco / ios 15.2(2)e8 15.2(2)e8.x
cisco / ios_xe 3.16.7bs 3.16.7bs.x
cisco / ios_xe 3.18.4sp 3.18.4sp.x
cisco / ios 15.2(6)e0a 15.2(6)e0a.x
cisco / ios 15.5(3)s7 15.5(3)s7.x
cisco / ios 15.3(3)jda15 15.3(3)jda15.x
cisco / ios 15.1(3)svm3 15.1(3)svm3.x
cisco / ios_xe 3.6.7be 3.6.7be.x
cisco / ios_xe 3.8.6e 3.8.6e.x
cisco / ios 15.3(3)ji2 15.3(3)ji2.x
cisco / ios_xe 16.5.3 16.5.3.x
cisco / ios_xe 3.18.1hsp 3.18.1hsp.x
cisco / ios_xe 3.10.1e 3.10.1e.x
cisco / ios 15.2(6)e1a 15.2(6)e1a.x
cisco / ios_xe 3.10.1ae 3.10.1ae.x
cisco / ios_xe 3.10.1se 3.10.1se.x
cisco / ios 15.2(6)e1s 15.2(6)e1s.x
cisco / ios 2.3 2.3.x

Frequently Asked Questions

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.