CVE-2026-77929CWE-434unrestricted-file-upload

CVE-2026-77929

High · published September 18, 2026

CVSS v3.1
8.8
EPSS
1%
Percentile
60.6
In the wild
Unconfirmed
What it is

ClipBucket v5 before 5.5.3-#182 contains a file upload vulnerability that allows authenticated users to achieve remote code execution by uploading a PHP file with valid image magic bytes through the photo upload endpoint. The FileUpload::manageFile() function in fileupload.class.php fails to update the file extension after MIME validation, allowing an attacker-controlled .php extension to persist on disk and execute as PHP via PHP-FPM when the uploaded file is retrieved.

The record
Technical detail
CVSS v3.1
8.8 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
8.7 · CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
EPSS
0.00941 · 60.6th percentile
Weakness
CWE-434 · Unrestricted Upload of File with Dangerous Type
Published
2026-09-18T19:17Z
References (3)
https://github.com/MacWarrior/clipbucket-v5/commit/61cce55ab26ef88fb782dfde47b44c17c56978cd · [email protected]https://github.com/MacWarrior/clipbucket-v5/releases/tag/5.5.3-%23182 · [email protected]https://www.vulncheck.com/advisories/clipbucket-remote-code-execution-via-photo-upload-endpoint · [email protected]
EPSS history
Timeline
  • 20 SEP 03:24Z
    EPSS moved — → 1%
    epss
  • 18 SEP 14:23Z
    ClipBucket < 5.5.3-#182 Remote Code Execution via Photo Upload Endpoint
    cvelistv5