CVE-2021-42114Public exploitNetwork attack vector

Privilege escalation via frequency-based TRR bypass

Published Nov 16, 2021 · Updated Sep 17, 2024

Rowhammer in DDR4 and LPDDR4 memory version 1 allows attackers to corrupt data and gain privileges via crafted memory-access patterns. Blacksmith varies the frequency, phase, amplitude, order, and intensity of accesses to aggressor rows, defeating Target Row Refresh and inducing bit flips in adjacent victim rows. Successful exploitation requires a hardware-specific hammering pattern; demonstrated consequences include page-table manipulation, root access through sudo, and recovery of an RSA private key across virtual machines.

CVSS severity9.0
Critical
EPSS probability2.98%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Rowhammer in DDR4 and LPDDR4 memory version 1 allows attackers to corrupt data and gain privileges via crafted memory-access patterns. Blacksmith varies the frequency, phase, amplitude, order, and intensity of accesses to aggressor rows, defeating Target Row Refresh and inducing bit flips in adjacent victim rows. Successful exploitation requires a hardware-specific hammering pattern; demonstrated consequences include page-table manipulation, root access through sudo, and recovery of an RSA private key across virtual machines.

The record

CVE
CVE-2021-42114
Published
Nov 16, 2021
Updated
Sep 17, 2024
Vendor
Micron Technology, Inc.
Product
LPDDR4
Classifications
CWE-20, T1068
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Nov 16, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 17, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Micron Technology, Inc. · LPDDR4version=1
SK hynix · DDR4 SDRAMversion=1
Micron Technology, Inc. · DDR4 SDRAMversion=1
Samsung Electronics · Samsung LPDDR4version=1
Samsung Electronics · Samsung DDR4version=1
SK hynix · LPDDR4version=1

Published CVSS scores

7.9NIST NVDAV:A/AC:M/Au:N/C:C/I:C/A:C
9.0NCSC Switzerland CNACVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
8.3NIST NVDCVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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 exploitPublished

Weakness, pattern, technique

CWE-20Improper Input Validation
T1068Exploitation for Privilege Escalation

Public exploit references

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

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo