CVE-2021-36865 | WordPress Quiz And Survey Master plugin <= 7.3.4 - Insecure direct object references (IDOR) vulnerability

Insecure direct object references (IDOR) vulnerability in ExpressTech Quiz And Survey Master plugin <= 7.3.4 at WordPress allows attackers to change the content of the quiz.

Published: 2022-09-30 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-36865 is rated Low Risk (26.7/100): CVSS Low severity, with low exploitation likelihood (EPSS 0.41%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-36865

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.14% 0.41% +0.27%
2 2025-10-06 0.22% 0.14% -0.08%
3 2025-10-05 — 0.22% —

Full EPSS history (11 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-36865

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
3.8 3.1 LOW
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:L Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:H)
They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
 1.2 2.5 [email protected]
4.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 1.4 [email protected]

Weakness enumeration for CVE-2021-36865

Affected software / configurations for CVE-2021-36865

Vendor Product Version Raw CPE
quizandsurveymaster quiz_and_survey_master <= 7.3.4 cpe:2.3:a:quizandsurveymaster:quiz_and_survey_master:*:*:*:*:*:wordpress:*:*

References for CVE-2021-36865

cvelogic Threat Intelligence