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.NET
.NET NuGet
Not in CISA KEV
MEDIUM severity

CVE-2019-9648 — CoreFtp

MEDIUM

CVE-2019-9648 is a medium-severity (CVSS 5.3) Path Traversal vulnerability in CoreFtp. 3 public exploit or proof-of-concept references are indexed, so weaponization risk is real. The records list no fixed version yet; check the vendor advisory below and apply the mitigations in the meantime.

CoreFTP Directory Traversal

Published
Updated
Affected
1 pkg
Patched
See advisory
Exploits
3 known
Exploitation data as of Oct 31, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗
14.3%probability of exploitation in next 30 days
Moderate Risk0.00%
Lower risk than most CVEs97th percentile — riskier than 97% of all scored CVEsHighest risk
12.7%15.6%18.5%21.3%19.7%14.3%May 26Aug 26Oct 26

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

1 pkg affected
.NETCoreFtp

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects NuGet packages — download data is not available via public APIs for these ecosystems.

Description

An issue was discovered in the SFTP Server component in Core FTP 2.0 Build 674. A directory traversal vulnerability exists using the SIZE command along with a \..\..\ substring, allowing an attacker to enumerate file existence based on the returned information.

Affected Packages

1 total
EcosystemPackageVulnerable rangeFix
.NETNuGetCoreFtpall versionsNo fix

Affected Products

1 product · 1 configurations
Application
core ftpcoreftp
1 version
2.0
Exploits & PoCs
3

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

EDB-46535doswindows

Core FTP Server FTP / SFTP Server v2 Build 674 - 'SIZE' Directory Traversal

by Kevin Randall · Mar 13, 2019

Exploit-DB Source

Detection & mitigation playbook

Open-source dependency

  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for CoreFtp, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

  2. Remediation status

    The records we use list no patched version of CoreFtp for CVE-2019-9648. Check the maintainer's advisory, and where your build allows, override or pin the dependency away from the vulnerable range.

  3. Mitigate without a patch

    Resolve every user-supplied path to its canonical form and reject anything that escapes the intended directory, and run the component under an account that has no read or write access outside the directory it legitimately serves.

Frequently Asked Questions

An issue was discovered in the SFTP Server component in Core FTP 2.0 Build 674. A directory traversal vulnerability exists using the SIZE command along with a `\..\..\` substring, allowing an attacker to enumerate file existence based on the returned information.
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CVE-2019-9648: CoreFtp: CoreFTP Directory Traversal