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TI-2019-15738 Aliases CVE-2019-25686GHSA-frgr-r4xw-r3ph

Core FTP 2.0 build 653 PBSZ Unauthenticated Denial of Service

Priority HIGH 77CWE-306Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Security bypass
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-306.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00474 41st percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by the CNA and NVD
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
CoreftpCore FTP2.0—No fix listedCNA
  • Core FTP VendorCoreftp Affected 2.0 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:coreftp:core_ftp:2.0:build_653:*:*:*:*:*:*2.0 build_653VulnerableCoreftp
  • cpe:2.3:a:coreftp:core_ftp:2.0:build_653:*:*:*:*:*:* Versions 2.0 build_653 Vulnerable ·Coreftp

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2019-25686
  2. 2026-10-03 Alias added: GHSA-frgr-r4xw-r3ph

References

Exploit 1

Other 2

  • TI-2019-15707 Core FTP/SFTP Server 1.2 Denial of Service via Buffer Overflow CVSS 4.0HIGH 8.7
  • TI-2018-08689 Core FTP LE version 2.2 Build 1921 is prone to a buffer overflow vulnerability that may… CVSS 3.0CRITICAL 9.8
  • TI-2009-03322 Stack-based buffer overflow in Core FTP 2.1 build 1612 allows user-assisted remote… CVSS 2.0HIGH 9.3
  • TI-2013-03432 Stack-based buffer overflow in Core FTP before 2.2 build 1785 allows remote FTP servers… CVSS 2.0HIGH 9.3
  • TI-2020-13650 Buffer overflow vulnerability in Core FTP Server v1.2 Build 583, via a crafted username. CVSS 3.1CRITICAL 9.8
  • TI-2018-14671 The server in Core FTP 2.0 build 653 on 32-bit platforms allows remote attackers to cause… CVSS 3.0HIGH 7.5
See all 17 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences