CVE-2020-35951Public exploitNetwork attack vector

Unauthenticated file deletion via unchecked AJAX path

Published Jan 1, 2021 · Updated Aug 4, 2024

Arbitrary file deletion in Quiz and Survey Master before 7.0.1 allows remote attackers to delete server files through an AJAX request. The qsm_remove_file_fd_question handler passes the attacker-controlled file_url value to wp_delete_file without verifying that the path belongs to a quiz upload. The unauthenticated AJAX action permits deletion of configuration files, causing a site outage and enabling replacement of the WordPress installation.

CVSS severity9.9
Critical
EPSS probability76.33%
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 Quiz and Survey Master before 7.0.1 allows remote attackers to delete server files through an AJAX request. The qsm_remove_file_fd_question handler passes the attacker-controlled file_url value to wp_delete_file without verifying that the path belongs to a quiz upload. The unauthenticated AJAX action permits deletion of configuration files, causing a site outage and enabling replacement of the WordPress installation.

The record

CVE
CVE-2020-35951
Published
Jan 1, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-306, T1485
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 1, 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

6.4NVDAV:N/AC:L/Au:N/C:N/I:P/A:P
9.9MITRECVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/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-306Missing Authentication for Critical Function
T1485Data Destruction

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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