CVE-2020-13665

Access bypass vulnerability in Drupal Core allows JSON:API when JSON:API is in read/write mode. Only sites that have the read_only set to FALSE under jsonapi.settings config are vulnerable. This issue affects: Drupal Drupal Core 8.8.x versions prior to 8.8.8; 8.9.x versions prior to 8.9.1; 9.0.x versions prior to 9.0.1.

Published: 2021-05-05 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2020-13665 is rated Moderate Risk (63/100): CVSS Critical severity, with medium exploitation likelihood (EPSS 1.27%). Review affected assets and schedule remediation.

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-2020-13665

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 0.58% 1.27% +0.69%
2 2025-12-28 0.55% 0.58% +0.03%
3 2025-12-27 — 0.55% —

Full EPSS history (17 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-13665

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H 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:N)
No account or special rights needed—anonymous or random user is enough.
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:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.9 [email protected]
7.5 2.0 HIGH
AV:N/AC:L/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 10.0 6.4 [email protected]

Weakness enumeration for CVE-2020-13665

GitHub Security Advisory for CVE-2020-13665

GHSA-wxqp-jwc9-g39x · Severity: critical · Ecosystem: composer — Drupal Core Access bypass vulnerability

OS Trackers for CVE-2020-13665

vendor priority summary link
ubuntu medium CVE-2020-13665 medium priority: Ubuntu including 1 source packages (drupal7), 12 status rows across 12 suites (bionic, eoan, focal, groovy, hirsute, impish, jammy, kinetic, lunar, trusty, upstream, xenial): DNE 9, not-affected 3. https://ubuntu.com/security/CVE-2020-13665

Affected software / configurations for CVE-2020-13665

Vendor Product Version Raw CPE
drupal drupal >= 8.8.0, < 8.8.8 cpe:2.3:a:drupal:drupal:*:*:*:*:*:*:*:*
drupal drupal >= 8.9.0, < 8.9.1 cpe:2.3:a:drupal:drupal:*:*:*:*:*:*:*:*
drupal drupal >= 9.0.0, < 9.0.1 cpe:2.3:a:drupal:drupal:*:*:*:*:*:*:*:*

References for CVE-2020-13665

URL Tags
https://www.drupal.org/sa-core-2020-006 Vendor Advisory
cvelogic Threat Intelligence