High severity · published Jul 15, 2026
CVE-2026-61457
Grav before 1.0.3 Remote Code Execution via File Upload Extension Bypass
8.8
CVSS
0.6%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 49% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
GR
grav · getgrav
before 1.0.3 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-61457
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-61457
github.com
https://github.com/getgrav/grav/security/advisories/GHSA-66v2-vxxf-xc3v
www.vulncheck.com
https://www.vulncheck.com/advisories/grav-before-remote-code-execution-via-file-upload-extension-bypass
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