CVE-2026-67607

LightFTP 2.3.1 contains a residual race condition vulnerability (an incomplete fix for CVE-2024-11144) in the worker_thread_cleanup() function of ftpserv.c that allows remote unauthenticated attackers to destabilize or crash the daemon by triggering unsynchronized access to shared per-connection state without holding the required mutex lock. Attackers can send a data-transfer command such as LIST followed immediately by ABOR to exploit the missing synchronization on shared context and detached thread id reuse, resulting in daemon destabilization or crash which can lead to a denial of service. The 2.3.1 patch only narrowed the timing window (an extra re-check and reordered cleanup), it never added the missing lock, so the underlying race remains.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/zeroscience/tuktam#real-world-case-study-lightftp-cve-2024-11144
https://www.vulncheck.com/advisories/lightftp-race-condition-dos-via-worker-thread-cleanup
https://github.com/zeroscience/tuktam#real-world-case-study-lightftp-cve-2024-11144

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-31 16:17

Updated : 2026-09-09 20:35

NVD link : CVE-2026-67607

Mitre link : CVE-2026-67607

CVE.ORG link : CVE-2026-67607

JSON object : View

Products Affected

No product.

CWE

CWE-367

Time-of-check Time-of-use (TOCTOU) Race Condition

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