Vulnerability Database

383,304

Total vulnerabilities in the database

CVE-2024-20307 — cisco / ios

Stack-based Buffer Overflow

A vulnerability in the IKEv1 fragmentation code of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a heap overflow, resulting in an affected device reloading.

This vulnerability exists because crafted, fragmented IKEv1 packets are not properly reassembled. An attacker could exploit this vulnerability by sending crafted UDP packets to an affected system. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.

Note: Only traffic that is directed to the affected system can be used to exploit this vulnerability. This vulnerability can be triggered by IPv4 and IPv6 traffic.

  • Published: Mar 27, 2024
  • Updated: Sep 13, 2026
  • CVE: CVE-2024-20307
  • Severity: Medium
  • Exploit:
  • CISA KEV:

CVSS v3:

  • Severity: Medium
  • Score: 6.8
  • AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H

CWEs:

Software Affected versions
cisco / ios = 15.1(2)sg8
cisco / ios = 15.1(2)sy8
cisco / ios = 15.1(2)sy9
cisco / ios = 15.1(2)sy10
cisco / ios = 15.1(2)sy11
cisco / ios = 15.1(2)sy12
cisco / ios = 15.1(2)sy13
cisco / ios = 15.1(2)sy14
cisco / ios = 15.1(2)sy15
cisco / ios = 15.1(2)sy16
cisco / ios = 15.2(1)sy3
cisco / ios = 15.2(1)sy4
cisco / ios = 15.2(1)sy5
cisco / ios = 15.2(1)sy6
cisco / ios = 15.2(1)sy7
cisco / ios = 15.2(1)sy8
cisco / ios = 15.2(3)e4
cisco / ios = 15.2(3)e5
cisco / ios = 15.2(4)e2
cisco / ios = 15.2(4)e3
cisco / ios = 15.2(4)e4
cisco / ios = 15.2(4)e5
cisco / ios = 15.2(4)e5a
cisco / ios = 15.2(4)e6
cisco / ios = 15.2(4)e7
cisco / ios = 15.2(4)e8
cisco / ios = 15.2(4)e9
cisco / ios = 15.2(4)e10
cisco / ios = 15.2(4)e10a
cisco / ios = 15.2(4)e10d
cisco / ios = 15.2(4)ea4
cisco / ios = 15.2(4)ea5
cisco / ios = 15.2(4)ea6
cisco / ios = 15.2(4)ea7
cisco / ios = 15.2(4)ea8
cisco / ios = 15.2(4)ea9
cisco / ios = 15.2(4)ea9a
cisco / ios = 15.2(4)ec1
cisco / ios = 15.2(4)ec2
cisco / ios = 15.2(4)m11
cisco / ios = 15.2(5)e
cisco / ios = 15.2(5)ea
cisco / ios = 15.2(5b)e
cisco / ios = 15.3(1)sy1
cisco / ios = 15.3(1)sy2
cisco / ios = 15.3(3)jpi11
cisco / ios = 15.3(3)m8
cisco / ios = 15.3(3)m8a
cisco / ios = 15.3(3)m9
cisco / ios = 15.3(3)m10
cisco / ios = 15.3(3)s8
cisco / ios = 15.3(3)s8a
cisco / ios = 15.3(3)s9
cisco / ios = 15.3(3)s10
cisco / ios = 15.4(1)sy
cisco / ios = 15.4(1)sy1
cisco / ios = 15.4(1)sy2
cisco / ios = 15.4(1)sy3
cisco / ios = 15.4(1)sy4
cisco / ios = 15.4(3)s6
cisco / ios = 15.4(3)s6a
cisco / ios = 15.4(3)s7
cisco / ios = 15.4(3)s8
cisco / ios = 15.4(3)s9
cisco / ios = 15.4(3)s10
cisco / ios = 15.5(1)s4
cisco / ios = 15.5(1)sy
cisco / ios = 15.5(1)sy1
cisco / ios = 15.5(1)sy2
cisco / ios = 15.5(1)sy3
cisco / ios = 15.5(1)sy4
cisco / ios = 15.5(1)sy5
cisco / ios = 15.5(1)sy6
cisco / ios = 15.5(1)sy7
cisco / ios = 15.5(1)sy8
cisco / ios = 15.5(1)sy9
cisco / ios = 15.5(1)sy10
cisco / ios = 15.5(1)sy11
cisco / ios = 15.5(2)s4
cisco / ios = 15.5(2)t4
cisco / ios = 15.5(3)m3
cisco / ios = 15.5(3)m4
cisco / ios = 15.5(3)m4a
cisco / ios = 15.5(3)m5
cisco / ios = 15.5(3)m6
cisco / ios = 15.5(3)m6a
cisco / ios = 15.5(3)m7
cisco / ios = 15.5(3)m8
cisco / ios = 15.5(3)m9
cisco / ios = 15.5(3)m10
cisco / ios = 15.5(3)s3
cisco / ios = 15.5(3)s4
cisco / ios = 15.5(3)s5
cisco / ios = 15.5(3)s6
cisco / ios = 15.5(3)s6a
cisco / ios = 15.5(3)s6b
cisco / ios = 15.5(3)s7
cisco / ios = 15.5(3)s8
cisco / ios = 15.5(3)s9
cisco / ios = 15.5(3)s9a
cisco / ios = 15.5(3)s10
cisco / ios = 15.7(3)m
cisco / ios = 15.7(3)m0a
cisco / ios = 15.7(3)m1
cisco / ios = 15.7(3)m2
cisco / ios = 15.7(3)m3
cisco / ios = 15.7(3)m4
cisco / ios = 15.7(3)m4a
cisco / ios = 15.7(3)m4b
cisco / ios = 15.7(3)m5
cisco / ios = 15.7(3)m6
cisco / ios = 15.7(3)m7
cisco / ios = 15.7(3)m8
cisco / ios = 15.7(3)m9
cisco / ios = 15.8(3)m
cisco / ios = 15.8(3)m0a
cisco / ios = 15.8(3)m0b
cisco / ios = 15.8(3)m1
cisco / ios = 15.8(3)m1a
cisco / ios = 15.8(3)m2
cisco / ios = 15.8(3)m2a
cisco / ios = 15.8(3)m3
cisco / ios = 15.8(3)m3a
cisco / ios = 15.8(3)m3b
cisco / ios = 15.8(3)m4
cisco / ios = 15.8(3)m5
cisco / ios = 15.8(3)m6
cisco / ios = 15.8(3)m7
cisco / ios = 15.8(3)m8
cisco / ios = 15.8(3)m9
cisco / ios = 15.8(3)m10
cisco / ios = 15.9(3)m
cisco / ios = 15.9(3)m0a
cisco / ios = 15.9(3)m1
cisco / ios = 15.9(3)m2
cisco / ios = 15.9(3)m2a
cisco / ios = 15.9(3)m3
cisco / ios = 15.9(3)m3a
cisco / ios = 15.9(3)m3b
cisco / ios = 15.9(3)m4
cisco / ios = 15.9(3)m4a
cisco / ios = 15.9(3)m5
cisco / ios = 15.9(3)m6
cisco / ios = 15.9(3)m6a
cisco / ios = 15.9(3)m6b
cisco / ios = 15.9(3)m7
cisco / ios = 15.9(3)m7a
cisco / ios_xe = 3.4.8sg
cisco / ios_xe = 3.7.4e
cisco / ios_xe = 3.7.5e
cisco / ios_xe = 3.8.2e
cisco / ios_xe = 3.8.3e
cisco / ios_xe = 3.8.4e
cisco / ios_xe = 3.8.5ae
cisco / ios_xe = 3.8.5e
cisco / ios_xe = 3.8.6e
cisco / ios_xe = 3.8.7e
cisco / ios_xe = 3.8.8e
cisco / ios_xe = 3.8.9e
cisco / ios_xe = 3.8.10e
cisco / ios_xe = 3.9.0e
cisco / ios_xe = 3.10.8as
cisco / ios_xe = 3.10.8s
cisco / ios_xe = 3.10.9s
cisco / ios_xe = 3.10.10s
cisco / ios_xe = 3.13.6as
cisco / ios_xe = 3.13.6s
cisco / ios_xe = 3.13.7as
cisco / ios_xe = 3.13.7s
cisco / ios_xe = 3.13.8s
cisco / ios_xe = 3.13.9s
cisco / ios_xe = 3.13.10s
cisco / ios_xe = 3.14.4s
cisco / ios_xe = 3.15.4s
cisco / ios_xe = 3.16.3as
cisco / ios_xe = 3.16.3s
cisco / ios_xe = 3.16.4as
cisco / ios_xe = 3.16.4bs
cisco / ios_xe = 3.16.4ds
cisco / ios_xe = 3.16.4s
cisco / ios_xe = 3.16.5s
cisco / ios_xe = 3.16.6bs
cisco / ios_xe = 3.16.6s
cisco / ios_xe = 3.16.7as
cisco / ios_xe = 3.16.7bs
cisco / ios_xe = 3.16.7s
cisco / ios_xe = 3.16.8s
cisco / ios_xe = 3.16.9s
cisco / ios_xe = 3.16.10s
cisco / ios_xe = 16.1.3
cisco / ios_xe = 16.2.1
cisco / ios_xe = 16.2.2
cisco / ios_xe = 16.3.1
cisco / ios_xe = 16.3.1a
cisco / ios_xe = 16.3.2
cisco / ios_xe = 16.3.3
cisco / ios_xe = 16.3.4
cisco / ios_xe = 16.3.5
cisco / ios_xe = 16.3.5b
cisco / ios_xe = 16.3.6
cisco / ios_xe = 16.3.7
cisco / ios_xe = 16.3.8
cisco / ios_xe = 16.3.9
cisco / ios_xe = 16.3.10
cisco / ios_xe = 16.3.11
cisco / ios_xe = 16.4.1
cisco / ios_xe = 16.4.2
cisco / ios_xe = 16.4.3
cisco / ios_xe = 16.5.1
cisco / ios_xe = 16.5.1a
cisco / ios_xe = 16.5.1b
cisco / ios_xe = 16.5.2
cisco / ios_xe = 16.5.3
cisco / ios_xe = 16.6.1
cisco / ios_xe = 16.6.2
cisco / ios_xe = 16.6.3
cisco / ios_xe = 16.6.4
cisco / ios_xe = 16.6.4a
cisco / ios_xe = 16.6.5
cisco / ios_xe = 16.6.5a
cisco / ios_xe = 16.6.6
cisco / ios_xe = 16.6.7
cisco / ios_xe = 16.6.8
cisco / ios_xe = 16.6.9
cisco / ios_xe = 16.6.10
cisco / ios_xe = 16.7.1
cisco / ios_xe = 16.7.1a
cisco / ios_xe = 16.7.1b
cisco / ios_xe = 16.7.2
cisco / ios_xe = 16.7.3
cisco / ios_xe = 16.7.4
cisco / ios_xe = 16.8.1
cisco / ios_xe = 16.8.1a
cisco / ios_xe = 16.8.1b
cisco / ios_xe = 16.8.1c
cisco / ios_xe = 16.8.1d
cisco / ios_xe = 16.8.1e
cisco / ios_xe = 16.8.1s
cisco / ios_xe = 16.8.2
cisco / ios_xe = 16.8.3
cisco / ios_xe = 16.9.1
cisco / ios_xe = 16.9.1a
cisco / ios_xe = 16.9.1b
cisco / ios_xe = 16.9.1s
cisco / ios_xe = 16.9.2
cisco / ios_xe = 16.9.3
cisco / ios_xe = 16.9.3a
cisco / ios_xe = 16.9.4
cisco / ios_xe = 16.9.5
cisco / ios_xe = 16.9.5f
cisco / ios_xe = 16.9.6
cisco / ios_xe = 16.9.7
cisco / ios_xe = 16.9.8
cisco / ios_xe = 16.10.1
cisco / ios_xe = 16.10.1a
cisco / ios_xe = 16.10.1b
cisco / ios_xe = 16.10.1c
cisco / ios_xe = 16.10.1d
cisco / ios_xe = 16.10.1e
cisco / ios_xe = 16.10.1f
cisco / ios_xe = 16.10.1g
cisco / ios_xe = 16.10.1s
cisco / ios_xe = 16.10.2
cisco / ios_xe = 16.10.3
cisco / ios_xe = 16.11.1
cisco / ios_xe = 16.11.1a
cisco / ios_xe = 16.11.1b
cisco / ios_xe = 16.11.1s
cisco / ios_xe = 16.11.2
cisco / ios_xe = 16.12.1
cisco / ios_xe = 16.12.1a
cisco / ios_xe = 16.12.1c
cisco / ios_xe = 16.12.1s
cisco / ios_xe = 16.12.1t
cisco / ios_xe = 16.12.1w
cisco / ios_xe = 16.12.1x
cisco / ios_xe = 16.12.1y
cisco / ios_xe = 16.12.1z1
cisco / ios_xe = 16.12.1z2
cisco / ios_xe = 16.12.2
cisco / ios_xe = 16.12.2a
cisco / ios_xe = 16.12.2s
cisco / ios_xe = 16.12.3
cisco / ios_xe = 16.12.3a
cisco / ios_xe = 16.12.3s
cisco / ios_xe = 16.12.4
cisco / ios_xe = 16.12.4a
cisco / ios_xe = 16.12.5
cisco / ios_xe = 16.12.5a
cisco / ios_xe = 16.12.5b
cisco / ios_xe = 16.12.6
cisco / ios_xe = 16.12.6a
cisco / ios_xe = 16.12.7
cisco / ios_xe = 16.12.8
cisco / ios_xe = 16.12.9
cisco / ios_xe = 17.1.1
cisco / ios_xe = 17.1.1a
cisco / ios_xe = 17.1.1s
cisco / ios_xe = 17.1.1t
cisco / ios_xe = 17.1.3
cisco / ios_xe = 17.2.1
cisco / ios_xe = 17.2.1a
cisco / ios_xe = 17.2.1r
cisco / ios_xe = 17.2.1v
cisco / ios_xe = 17.2.2
cisco / ios_xe = 17.2.3
cisco / ios_xe = 17.3.1
cisco / ios_xe = 17.3.1a
cisco / ios_xe = 17.3.1w
cisco / ios_xe = 17.3.1x
cisco / ios_xe = 17.3.1z
cisco / ios_xe = 17.3.2
cisco / ios_xe = 17.3.2a
cisco / ios_xe = 17.3.3
cisco / ios_xe = 17.3.4
cisco / ios_xe = 17.3.4a
cisco / ios_xe = 17.3.4b
cisco / ios_xe = 17.3.4c
cisco / ios_xe = 17.3.5
cisco / ios_xe = 17.3.5a
cisco / ios_xe = 17.3.5b
cisco / ios_xe = 17.3.6
cisco / ios_xe = 17.3.7
cisco / ios_xe = 17.4.1
cisco / ios_xe = 17.4.1a
cisco / ios_xe = 17.4.1b
cisco / ios_xe = 17.4.2
cisco / ios_xe = 17.4.2a
cisco / ios_xe = 17.5.1
cisco / ios_xe = 17.5.1a
cisco / ios_xe = 17.6.1
cisco / ios_xe = 17.6.1a
cisco / ios_xe = 17.6.1w
cisco / ios_xe = 17.6.1x
cisco / ios_xe = 17.6.1y
cisco / ios_xe = 17.6.1z
cisco / ios_xe = 17.6.1z1
cisco / ios_xe = 17.6.2
cisco / ios_xe = 17.6.3
cisco / ios_xe = 17.6.3a
cisco / ios_xe = 17.6.4
cisco / ios_xe = 17.6.5
cisco / ios_xe = 17.6.5a
cisco / ios_xe = 17.7.1
cisco / ios_xe = 17.7.1a
cisco / ios_xe = 17.7.1b
cisco / ios_xe = 17.7.2
cisco / ios_xe = 17.8.1
cisco / ios_xe = 17.8.1a
cisco / ios_xe = 17.9.1
cisco / ios_xe = 17.9.1a
cisco / ios_xe = 17.9.1w
cisco / ios_xe = 17.9.1x
cisco / ios_xe = 17.9.1x1
cisco / ios_xe = 17.9.1y
cisco / ios_xe = 17.9.2
cisco / ios_xe = 17.9.2a
cisco / ios_xe = 17.9.3
cisco / ios_xe = 17.9.3a
cisco / ios_xe = 17.10.1
cisco / ios_xe = 17.10.1a
cisco / ios_xe = 17.10.1b
cisco / ios_xe = 17.11.1
cisco / ios_xe = 17.11.1a
cisco / ios_xe = 17.11.99sw

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.