8.8
HIGH CVSS 3.1
CVE-2026-61457
Grav before 1.0.3 Remote Code Execution via File Upload Extension Bypass
Description

The Grav API plugin (getgrav/grav-plugin-api) before 1.0.3 contains a file upload extension bypass in the API media controller. HandlesMediaUploads::validateFileExtension() inspects only the final file extension via pathinfo($filename, PATHINFO_EXTENSION), so a user with api.media.write permission can upload a file with a double extension such as shell.php.jpg to bypass the dangerous extensions blocklist. The web server may then execute the file as PHP, resulting in remote code execution.

INFO

Published Date :

July 15, 2026, 12:18 p.m.

Last Modified :

July 15, 2026, 1:17 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-61457 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Getgrav grav
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 3.1 HIGH [email protected]
CVSS 4.0 MEDIUM 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 MEDIUM [email protected]
Solution
Update the Grav API plugin to version 1.0.3 to fix file upload validation issues.
  • Update the Grav API plugin to version 1.0.3.
  • Verify file upload validation logic.
  • Remove write permissions if not required.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-61457.

URL Resource
https://github.com/getgrav/grav/security/advisories/GHSA-66v2-vxxf-xc3v
https://www.vulncheck.com/advisories/grav-before-remote-code-execution-via-file-upload-extension-bypass
https://github.com/getgrav/grav/security/advisories/GHSA-66v2-vxxf-xc3v
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-61457 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-61457 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-61457 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-61457 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Jul. 15, 2026

    Action Type Old Value New Value
    Added Reference https://github.com/getgrav/grav/security/advisories/GHSA-66v2-vxxf-xc3v
    Added SSVC {'id': 'CVE-2026-61457', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-07-15T12:12:45.122123Z'}
  • New CVE Received by [email protected]

    Jul. 15, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'getgrav', 'product': 'grav', 'versions': [{'status': 'affected', 'version': '0', 'lessThan': '1.0.3', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '1.0.3', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}]
    Added Description The Grav API plugin (getgrav/grav-plugin-api) before 1.0.3 contains a file upload extension bypass in the API media controller. HandlesMediaUploads::validateFileExtension() inspects only the final file extension via pathinfo($filename, PATHINFO_EXTENSION), so a user with api.media.write permission can upload a file with a double extension such as shell.php.jpg to bypass the dangerous extensions blocklist. The web server may then execute the file as PHP, resulting in remote code execution.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
    Added CWE CWE-434
    Added Reference https://github.com/getgrav/grav/security/advisories/GHSA-66v2-vxxf-xc3v
    Added Reference https://www.vulncheck.com/advisories/grav-before-remote-code-execution-via-file-upload-extension-bypass
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.