How severe is CVE-2019-6340?

CVE-2019-6340 has a CVSS score of 8.1/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2019-6340?

CVE-2019-6340 affects the following packages: drupal/core (Packagist), drupal/core (Packagist), drupal/core (Packagist), drupal/drupal (Packagist), drupal/drupal (Packagist), drupal/drupal (Packagist). Ecosystems affected: Packagist.

How do I fix CVE-2019-6340?

Update drupal/core to 8.6.10 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2019-6340 is resolved across your whole dependency graph.

How do I detect CVE-2019-6340 in my Packagist dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for drupal/core, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2019-6340 if there is no patch (or I can't update yet)?

Do not deserialise data from untrusted sources: where the format allows it, restrict deserialisation to an explicit allowlist of expected types, and prefer a data-only format (JSON, Protobuf) over one that can reconstruct arbitrary objects until you can upgrade.

Is CVE-2019-6340 actively exploited in the wild?

Yes. There are 24 known exploit references for CVE-2019-6340, including 3 documented proof-of-concept exploits on Exploit-DB and 16 in-the-wild exploitations observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for CVE-2019-6340?

CVE-2019-6340 has an EPSS (Exploit Prediction Scoring System) score of 92.0%, placing it in the 100th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. A score above 50% indicates significantly elevated exploitation risk — immediate patching is strongly recommended.

Is CVE-2019-6340 in the CISA Known Exploited Vulnerabilities catalog?

Yes. CVE-2019-6340 (Drupal Core Remote Code Execution Vulnerability) was added to CISA's Known Exploited Vulnerabilities (KEV) catalog on 2022-03-25. CISA required all US federal civilian agencies to remediate this vulnerability by 2022-04-15. The required action was: Apply updates per vendor instructions. Being listed in the KEV catalog is the strongest possible confirmation of active exploitation — treat this as a critical priority.

What type of vulnerability is CVE-2019-6340?

CVE-2019-6340 is classified as Deserialization of Untrusted Data (CWE-502). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

Is there exploit tooling available for CVE-2019-6340?

A Nuclei detection template exists for CVE-2019-6340, meaning automated scanners can fingerprint it. Public exploit tooling significantly increases real-world risk — prioritize patching and ensure detection coverage. Exploit tooling should only ever be used in isolated, authorized testing environments.

When was CVE-2019-6340 published, and has it been updated?

CVE-2019-6340 was published on February 21, 2019 and was last updated on October 24, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐘

🐘 Packagist

CISA KEV · ACTIVELY EXPLOITED

HIGH severity

CVE-2019-6340 — core

HIGH

CVE-2019-6340 is a high-severity (CVSS 8.1) Deserialization of Untrusted Data vulnerability in drupal/core. It is in CISA's Known Exploited Vulnerabilities catalog (added 2022-03-25) — treat it as actively exploited and patch now. A fix is available for drupal/core — see the affected versions and patch details below.

Drupal Core Remote Code Execution Vulnerability

Also known asDRUPAL-CORE-2019-003GHSA-3gx6-h57h-rm27

Published

Feb 21, 2019

Updated

Oct 24, 2026

Affected

6 pkgs

Patched

6 / 6

Exploits

24 known

Exploitation data as of Oct 23, 2026 · OSV.dev, NVD, CISA KEV, FIRST.org (EPSS)

Exploitation Status

Actively exploited in the wild

Confirmed by CISA's Known Exploited Vulnerabilities catalog on 2022-03-25. Federal agencies were required to remediate by 2022-04-15.
A successful exploit gives an attacker total control of the affected component, not partial access.

Exploitation and automatability from CISA (KEV catalog and SSVC triage) for CVE-2019-6340.

EPSS Exploitation Probability

via FIRST.org ↗

92.0%probability of exploitation in next 30 days

Very High Risk0.00%

Lower risk than most CVEs100th percentile — riskier than 100% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

CVE-2019-6340 by exploitation likelihood (EPSS) against impact (CVSS). In the shaded patch-first corner (EPSS 50%+, CVSS 7.0+).

Where this sits among everything scored

Of 394,803 CVEs with a current EPSS score, this one falls in the ≥ 90% band (highlighted). Counts from FIRST.org, log-scaled.

Real-World Exposure

6 pkgs affected

🐘drupal/core🐘drupal/core🐘drupal/core🐘drupal/drupal🐘drupal/drupal🐘drupal/drupal

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.

Description

Some field types do not properly sanitize data from non-form sources in Drupal 8.5.x before 8.5.11 and Drupal 8.6.x before 8.6.10. This can lead to arbitrary PHP code execution in some cases. A site is only affected by this if one of the following conditions is met: The site has the Drupal 8 core RESTful Web Services (rest) module enabled and allows PATCH or POST requests, or the site has another web services module enabled, like JSON:API in Drupal 8, or Services or RESTful Web Services in Drupal 7. (Note: The Drupal 7 Services module itself does not require an update at this time, but you should apply other contributed updates associated with this advisory if Services is in use.)

Affected Packages

6 total 6 fixed

Ecosystem	Package	Vulnerable range	Fix
🐘Packagist	`drupal/core`	≥ 8.6.0&&< 8.6.10	8.6.10`composer require drupal/core:^8.6.10`
🐘Packagist	`drupal/core`	≥ 7.0.0&&< 7.62.0	7.62.0`composer require drupal/core:^7.62.0`
🐘Packagist	`drupal/core`	≥ 8.0.0&&< 8.5.11	8.5.11`composer require drupal/core:^8.5.11`
🐘Packagist	`drupal/drupal`	≥ 7.0.0&&< 7.62.0	7.62.0`composer require drupal/drupal:^7.62.0`
🐘Packagist	`drupal/drupal`	≥ 8.0.0&&< 8.5.11	8.5.11`composer require drupal/drupal:^8.5.11`
🐘Packagist	`drupal/drupal`	≥ 8.6.0&&< 8.6.10	8.6.10`composer require drupal/drupal:^8.6.10`

Affected Products

1 product · 2 configurations

Application

drupaldrupal

≥ 8.6.0 && < 8.6.10

range

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

EDB-46459webappsphp

Drupal < 8.6.9 - REST Module Remote Code Execution

by leonjza · Feb 25, 2019

Exploit-DB Source

EDB-46452webappsphp

Drupal < 8.6.10 / < 8.5.11 - REST Module Remote Code Execution

by Charles Fol · Feb 23, 2019

Exploit-DB Source

EDB-46510remotephp✓ Verified

Drupal < 8.5.11 / < 8.6.10 - RESTful Web Services unserialize() Remote Command Execution (Metasploit)

by Metasploit · Mar 7, 2019

Exploit-DB Source

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for drupal/core, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update drupal/core to 8.6.10 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2019-6340 is resolved across your whole dependency graph.
Workarounds
Do not deserialise data from untrusted sources: where the format allows it, restrict deserialisation to an explicit allowlist of expected types, and prefer a data-only format (JSON, Protobuf) over one that can reconstruct arbitrary objects until you can upgrade.

How to detect CVE-2019-6340

A community-maintained Nuclei template exists for this CVE. You can scan for it directly:

nuclei -id cve-2019-6340 -u https://target

Template: Drupal - Remote Code Execution
Severity: high
Impact: Successful exploitation of this vulnerability could allow an attacker to execute arbitrary code on the affected Drupal site.
Remediation: Apply the official security patch provided by Drupal to fix the deserialization vulnerability.

Template by ProjectDiscovery nuclei-templates (madrobot), MIT licensed. View the full template. Scan only systems you are authorised to test.

Frequently Asked Questions

O3 Security · Impact-Aware SCA

Is CVE-2019-6340 in your dependencies?

Find it across Packagist, including transitive dependencies.

Scan my dependencies How O3 SCA works

CVSS Score

8.1/10CVSS v3 base

Vector breakdown

Attack Vector

Network

Attack Complexity

High

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Raw vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

CWE Classification

CWE-502Deserialization of Untrusted Data

Weaponization

OpenSSF Scorecard

Package health score

security-advisories

4.8/10

Maintained10/10

Code-Review10/10

Branch-Protection0/10

Assessed Oct 19, 2026

Timeline

Disclosed

Feb 21, 2019

First exploit

Feb 25, 2019

3 days after disclosure — rapid exploitation

KEV added

Mar 25, 2022

Last updated

Oct 24, 2026

Identifiers

CVE-2019-6340

GHSA-3gx6-h57h-rm27

DRUPAL-CORE-2019-003

References

Advisorysecurityfocus.com Advisorydrupal.org Advisorysynology.com Advisorynvd.nist.gov Fixexploit-db.com Webcisa.gov Webgithub.com Webgithub.com Webexploit-db.com Webexploit-db.com Webexploit-db.com Packagegithub.com Evidenceexploit-db.com Evidenceexploit-db.com

Related vulnerabilities

This CVE is high severity; 1 of 8 other CVEs affecting drupal/core is rated as high or higher (top: critical).

CVE-2026-6365CVE-2026-9082CVE-2026-6367CVE-2026-6366CVE-2025-13080CVE-2025-13082CVE-2025-13081CVE-2025-13083

Provenance

Sources

OSV.devNVDCISA KEVFIRST.org (EPSS)

Last verifiedOct 24, 2026

CVE-2019-6340 — core

Exploitation Status

Actively exploited in the wild

EPSS Exploitation Probability

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

Description

Affected Packages

Affected Products

Detection & mitigation playbook

Detect

Fix

Workarounds

How to detect CVE-2019-6340

Frequently Asked Questions

Is CVE-2019-6340 in your dependencies?