CVE-2026-67607 (GCVE-0-2026-67607)

Vulnerability from cvelistv5 – Published: 2026-07-31 15:59 – Updated: 2026-08-14 16:50 X_Open Source
VLAI
Title
LightFTP 2.3.1 Race Condition DoS via worker_thread_cleanup
Summary
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.
Severity
8.2 (High)
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-31 16:17 UTC
CWE
  • CWE-367 - Time-of-check Time-of-use (TOCTOU) Race Condition
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 8103 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
hfiref0x LightFTP Affected: 0 , ≤ 2.3.1 (semver)
    cpe:2.3:a:hfiref0x:lightftp:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-07-30 00:00
Credits
Gjoko Krstic of Zero Science Lab
Show details on NVD website
To clipboard 

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    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.