CVE-2021-45608Network attack vector

Kernel memory corruption via unchecked allocation length

Published Dec 26, 2021 · Updated Aug 4, 2024

Integer overflow in KCodes NetUSB on affected router firmware allows remote attackers to corrupt kernel memory via TCP port 20005. SoftwareBus_dispatchNormalEPMsgOut adds 0x11 to an unchecked 32-bit length for kmalloc, then receives attacker-controlled data using the original larger length. The service must be reachable, and reliable kernel code execution depends on complex remote heap shaping.

CVSS severity6.5
Medium
EPSS probability2.51%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Integer overflow in KCodes NetUSB on affected router firmware allows remote attackers to corrupt kernel memory via TCP port 20005. SoftwareBus_dispatchNormalEPMsgOut adds 0x11 to an unchecked 32-bit length for kmalloc, then receives attacker-controlled data using the original larger length. The service must be reachable, and reliable kernel code execution depends on complex remote heap shaping.

The record

CVE
CVE-2021-45608
Published
Dec 26, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-190, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 26, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

6.5NETGEARCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N
6.5MITRECVSS:3.1/AC:H/AV:N/A:N/C:H/I:L/PR:N/S:U/UI:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-190Integer Overflow or Wraparound
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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