CVE-2020-21554Network attack vector

Authenticated arbitrary file deletion via back_list

Published Mar 25, 2022 · Updated Aug 4, 2024

Arbitrary file deletion in TinyShop 3.1.1 allows remote authenticated users to delete server files through the back_list parameter. The administrative controller in controllers\admin.php uses the attacker-controlled value as a deletion target without restricting the requested path. An authenticated account is required; deletion can remove configuration or application files, including install.lock, and reopen CMS installation.

CVSS severity8.1
High
EPSS probability1.52%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Arbitrary file deletion in TinyShop 3.1.1 allows remote authenticated users to delete server files through the back_list parameter. The administrative controller in controllers\admin.php uses the attacker-controlled value as a deletion target without restricting the requested path. An authenticated account is required; deletion can remove configuration or application files, including install.lock, and reopen CMS installation.

The record

CVE
CVE-2020-21554
Published
Mar 25, 2022
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
T1070.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Mar 25, 2022CVE 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 privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.5NIST NVDAV:N/AC:L/Au:S/C:N/I:P/A:P
8.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1070.004File Deletion

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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