CVE intelligence and bounded remediation

CVE-2024-20308 — Cisco Ios security vulnerability

High CVSS 8.6

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 underflow, 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 denial of service (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..

Severity
High
CVSS
8.6 (3.1)
Published
2024-03-27
CISA KEV
Not currently listed
Ecosystem
operating-system
Weaknesses
CWE-787

Affected products

  • cisco / ios / 12.4(22)md
  • cisco / ios / 12.4(22)md1
  • cisco / ios / 12.4(22)md2
  • cisco / ios / 12.4(22)mda
  • cisco / ios / 12.4(22)mda1
  • cisco / ios / 12.4(22)mda2

Showing 6 representative product identities from 1012 source matches. Confirm exact affected versions with the linked vendor and NVD evidence.

Matched remediation archetype

Buffer bounds, memory safety, and memory corruption

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Identify affected native-code versions, build flags, architectures, parsers, codecs, drivers, and input paths in all shipped artifacts.
  • Determine whether untrusted data reaches the affected routine and the process privilege, sandbox, and network exposure.
  • Confirm statically linked, vendored, firmware, and platform-provided copies, not only package-manager records.

Remediate safely

  • Apply the maintained upstream correction or replace the affected component, then rebuild every dependent artifact from clean inputs.
  • Adopt bounds-checked interfaces, validated sizes and integer conversions, clear ownership, and memory-safe components where practical.
  • Enable supported compiler and runtime hardening and add sanitized tests and fuzz regression seeds derived from non-weaponized fixtures.

Authoritative sources

Complete CVE record and remediation plan

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