CVE-2023-25655 is a critical-severity (CVSS 9.8) Unrestricted File Upload vulnerability in baserproject/basercms. A fix is available for baserproject/basercms — see the affected versions and patch details below.
baserCMS allows any file to be uploaded
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2023-25655.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
baserproject/basercmsReal-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
There is a vulnerability that allows uploading any files to baserCMS.
This is a vulnerability that needs to be addressed when the management system is used by an unspecified number of users. If you are eligible, please update to the new version as soon as possible.
Target
baserCMS 4.7.3 and earlier versions
Vulnerability
Malicious files may be uploaded in Upload File Management.
Countermeasures
Update to the latest version of baserCMS
Please refer to the following page to reference for more information. https://basercms.net/security/JVN_61105618
Credits
- Taisei Inoue@GMO Cybersecurity by Ierae, Inc.
- Yusuke Akagi@Mitsui Bussan Secure Directions, Inc.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | baserproject/basercms | all versions | 4.7.5composer require baserproject/basercms:^4.7.5 |
Affected Products
basercmsbasercmsDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for baserproject/basercms, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update baserproject/basercms to 4.7.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-25655 is resolved across your whole dependency graph.
Workarounds
Treat uploaded files as untrusted until proven otherwise: validate the actual content type rather than the supplied extension, store uploads outside the web root on a volume mounted without execute permission, and rename them to server-generated identifiers so an attacker cannot choose the path a request will later resolve.
Frequently Asked Questions
Is CVE-2023-25655 in your dependencies?
Find it across Packagist, including transitive dependencies.