CVE-2019-25686
Core FTP 2.0 build 653 PBSZ Unauthenticated Denial of Service
Description
Core FTP 2.0 build 653 contains a denial of service vulnerability in the PBSZ command that allows unauthenticated attackers to crash the service by sending a malformed command with an oversized buffer. Attackers can send a PBSZ command with a payload exceeding 211 bytes to trigger an access violation and crash the FTP server process.
INFO
Published Date :
April 5, 2026, 9:16 p.m.
Last Modified :
July 24, 2026, 10:10 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | HIGH | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 4.0 | HIGH | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 4.0 | HIGH | [email protected] |
Solution
- Apply the latest update for Core FTP.
- Ensure PBSZ command input is validated.
- Restrict access to FTP services.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2019-25686.
| URL | Resource |
|---|---|
| http://coreftp.com/server/download/archive/CoreFTPServer653.exe | Product |
| http://www.coreftp.com/ | Product |
| https://www.exploit-db.com/exploits/46532 | Exploit VDB Entry |
| https://www.vulncheck.com/advisories/core-ftp-build-653-pbsz-unauthenticated-denial-of-service | Third Party Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2019-25686 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2019-25686
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2019-25686 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2019-25686 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Translated by [email protected]
Jul. 24, 2026
Action Type Old Value New Value Added Translation Title: Core FTP de Coreftp, Description: Core FTP 2.0 build 653 contiene una vulnerabilidad de denegación de servicio en el comando PBSZ que permite a atacantes no autenticados bloquear el servicio enviando un comando malformado con un búfer sobredimensionado. Los atacantes pueden enviar un comando PBSZ con una carga útil que excede los 211 bytes para desencadenar una violación de acceso y bloquear el proceso del servidor FTP. -
CVE Modified by [email protected]
Jun. 17, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'Coreftp', 'product': 'Core FTP', 'versions': [{'status': 'affected', 'version': '2.0'}]}] -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 17, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2019-25686', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-04-06T15:42:59.651605Z'} -
Initial Analysis by [email protected]
Apr. 09, 2026
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:coreftp:core_ftp:2.0:build_653:*:*:*:*:*:* Added Reference Type VulnCheck: http://coreftp.com/server/download/archive/CoreFTPServer653.exe Types: Product Added Reference Type VulnCheck: http://www.coreftp.com/ Types: Product Added Reference Type VulnCheck: https://www.exploit-db.com/exploits/46532 Types: Exploit, VDB Entry Added Reference Type VulnCheck: https://www.vulncheck.com/advisories/core-ftp-build-653-pbsz-unauthenticated-denial-of-service Types: Third Party Advisory -
New CVE Received by [email protected]
Apr. 05, 2026
Action Type Old Value New Value Added Description Core FTP 2.0 build 653 contains a denial of service vulnerability in the PBSZ command that allows unauthenticated attackers to crash the service by sending a malformed command with an oversized buffer. Attackers can send a PBSZ command with a payload exceeding 211 bytes to trigger an access violation and crash the FTP server process. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Added CWE CWE-306 Added Reference http://coreftp.com/server/download/archive/CoreFTPServer653.exe Added Reference http://www.coreftp.com/ Added Reference https://www.exploit-db.com/exploits/46532 Added Reference https://www.vulncheck.com/advisories/core-ftp-build-653-pbsz-unauthenticated-denial-of-service