How severe is CVE-2020-35951?

CVE-2020-35951 has a CVSS 3.x base score of 9.9, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability high.

Is CVE-2020-35951 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 76% (99th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-35951?

CVE-2020-35951 affects Expresstech Quiz And Survey Master. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-35951?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2020-35951 published?

CVE-2020-35951 was published on 2021-01-01 and last updated on 2026-06-17.

CVE-2020-35951

CVE-2020-35951 is a critical-severity vulnerability in Expresstech Quiz And Survey Master with a CVSS 3.x base score of 9.9. Its EPSS exploit-prediction score of 76% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-306.

Key facts

Severity: Critical (CVSS 3.x base score 9.9)
CVSS v2: 6.4
EPSS exploit prediction: 76% (99th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-306
Affected product: Expresstech Quiz And Survey Master
Published: 2021-01-01
Last modified: 2026-06-17

Description

An issue was discovered in the Quiz and Survey Master plugin before 7.0.1 for WordPress. It allows users to delete arbitrary files such as wp-config.php file, which could effectively take a site offline and allow an attacker to reinstall with a WordPress instance under their control. This occurred via qsm_remove_file_fd_question, which allowed unauthenticated deletions (even though it was only intended for a person to delete their own quiz-answer files).

Frequently asked questions

What is CVE-2020-35951?: An issue was discovered in the Quiz and Survey Master plugin before 7.0.1 for WordPress. It allows users to delete arbitrary files such as wp-config.php file, which could effectively take a site offline and allow an attacker to reinstall with a WordPress instance under their control. This occurred via qsm_remove_file_fd_question, which allowed unauthenticated deletions (even though it was only intended for a person to delete their own quiz-answer files).
How severe is CVE-2020-35951?: CVE-2020-35951 has a CVSS 3.x base score of 9.9, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability high.
Is CVE-2020-35951 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 76% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-35951?: CVE-2020-35951 affects Expresstech Quiz And Survey Master. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-35951?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2020-35951 published?: CVE-2020-35951 was published on 2021-01-01 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:expresstech:quiz_and_survey_master:*:*:*:*:*:wordpress:*:*

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