CVE-2026-70637 (GCVE-0-2026-70637)

Vulnerability from cvelistv5 – Published: 2026-08-06 14:15 – Updated: 2026-08-14 16:51 X_Open Source
VLAI
Title
LightFTP 2.4 Data Race Condition via ABOR Command in ftpserv.c
Summary
LightFTP through 2.4 contains multiple data race vulnerabilities in ftpserv.c that allow anonymous attackers to cause undefined behavior by issuing LIST followed by ABOR commands without authentication. The control thread closes data_socket and file_fd descriptors while worker threads concurrently operate on the same fields in worker_thread_cleanup, allowing stale file descriptors to be reassigned by the OS and subsequently used by worker threads on unrelated resources, resulting in potential denial of service.
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: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-06 17:23 UTC
CWE
  • CWE-820 - Missing Synchronization
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 6753 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
hfiref0x LightFTP Affected: 0 , ≤ 2.4 (custom)
Affected: 0 , ≤ d28c5e08aa4bd128737d35cc6ee0f9630a910ed5 (git)
    cpe:2.3:a:hfiref0x:lightftp:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-06-22 00:00
Credits
grant_Y (@grant-yim) Gjoko Krstic of Zero Science Lab
Show details on NVD website
To clipboard 

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