CVE-2021-27903Network attack vector

Server code execution via unrestricted Local volume paths

Published Jun 30, 2021 · Updated Aug 3, 2024

Remote code execution in Craft CMS before 3.6.7 allows remote attackers with a hijacked administrator session to run server-side code. The Local volume configuration accepted a File System Path inside system directories, allowing managed files to be written into sensitive application paths. Exploitation requires a hijacked administrator session and a site that permits administrative changes; successful abuse runs code in the web server context.

CVSS severity9.8
Critical
EPSS probability2.82%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Remote code execution in Craft CMS before 3.6.7 allows remote attackers with a hijacked administrator session to run server-side code. The Local volume configuration accepted a File System Path inside system directories, allowing managed files to be written into sensitive application paths. Exploitation requires a hijacked administrator session and a site that permits administrative changes; successful abuse runs code in the web server context.

The record

CVE
CVE-2021-27903
Published
Jun 30, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-862
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 30, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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 privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.5NIST NVDAV:N/AC:L/Au:N/C:P/I:P/A:P

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-862Missing Authorization

Public exploit references

No public exploit references are available in this record.

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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