CVE-2020-5295 is a medium-severity (CVSS 4.9) CWE-98 vulnerability in october/cms. 3 public exploit references exist, so weaponization risk is real. A fix is available for october/cms — see the affected versions and patch details below.
Local File read vulnerability in OctoberCMS
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2020-5295 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,636 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
october/cmsReal-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
Impact
An attacker can exploit this vulnerability to read local files of an October CMS server. The vulnerability is only exploitable by an authenticated backend user with the cms.manage_assets permission.
Patches
Issue has been patched in Build 466 (v1.0.466).
Workarounds
Apply https://github.com/octobercms/october/commit/2b8939cc8b5b6fe81e093fe2c9f883ada4e3c8cc to your installation manually if unable to upgrade to Build 466.
References
Reported by Sivanesh Ashok
For more information
If you have any questions or comments about this advisory:
- Email us at [email protected]
Threat assessment:
<img width="1108" alt="Screen Shot 2020-03-31 at 2 37 53 PM" src="https://user-images.githubusercontent.com/7253840/78072989-44b3ac80-735d-11ea-8676-09c69f0409c4.png">Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | october/cms | ≥ 1.0.319&&< 1.0.466 | 1.0.466composer require october/cms:^1.0.466 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
October CMS Build 465 - Arbitrary File Read Exploit (Authenticated)
by Sivanesh Ashok · Nov 13, 2020
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for october/cms, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update october/cms to 1.0.466 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-5295 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2020-5295 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2020-5295. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2020-5295 in your dependencies?
O3 Security finds CVE-2020-5295 across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.