CVE-2021-33887Public exploit

Physical boot of modified kernel via authenticity bypass

Published Jun 15, 2021 · Updated Aug 4, 2024

Insufficient verification of data authenticity in Peloton TTR01 through PTV55G allows attackers with physical access to boot modified kernel/ramdisk. The boot process accepts a modified kernel or ramdisk without authenticating the bootloader state. Physical access is required, and the attacker can alter confidentiality, integrity, and availability by running modified firmware.

CVSS severity6.8
Medium
EPSS probability0.27%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Insufficient verification of data authenticity in Peloton TTR01 through PTV55G allows attackers with physical access to boot modified kernel/ramdisk. The boot process accepts a modified kernel or ramdisk without authenticating the bootloader state. Physical access is required, and the attacker can alter confidentiality, integrity, and availability by running modified firmware.

The record

CVE
CVE-2021-33887
Published
Jun 15, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-345, T1601.001
Attack vector
physical
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 15, 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 vectorphysical
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.2NIST NVDAV:L/AC:L/Au:N/C:C/I:C/A:C
6.8NIST NVDCVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/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.

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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)
Vectorphysical
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-345Insufficient Verification of Data Authenticity
T1601.001Patch System Image

Public exploit references

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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