CVE-2021-33098

Host kernel crash via unchecked VF MTU

Published Nov 17, 2021 · Updated Aug 3, 2024

Improper input validation in Intel Ethernet 500 Series Controllers driver before 3.17.3 allows local users to crash the host kernel. The ixgbe_set_vf_lpe handler accepted a VF-supplied frame size before validating its supported range and attempted to update host NIC registers. A guest OS user able to change an SR-IOV VF MTU to an unsupported value can crash the host kernel, interrupting all workloads on that host.

CVSS severity6.5
Medium
EPSS probability0.31%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in Intel Ethernet 500 Series Controllers driver before 3.17.3 allows local users to crash the host kernel. The ixgbe_set_vf_lpe handler accepted a VF-supplied frame size before validating its supported range and attempted to update host NIC registers. A guest OS user able to change an SR-IOV VF MTU to an unsupported value can crash the host kernel, interrupting all workloads on that host.

The record

CVE
CVE-2021-33098
Published
Nov 17, 2021
Updated
Aug 3, 2024
Vendor
Intel
Product
Intel Ethernet 500 Series Controllers driver
Classifications
CWE-20, T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Nov 17, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=before version 3.17.3

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Intel · Intel Ethernet 500 Series Controllers driverversion=before version 3.17.3

Published CVSS scores

5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
6.5IntelCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H
4.9NIST NVDAV:L/AC:L/Au:N/C:N/I:N/A:C

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)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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