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TI-2026-47761 Aliases CVE-2026-67607GHSA-857x-mm78-cq2m

LightFTP 2.3.1 Race Condition DoS via worker_thread_cleanup

Priority HIGH 75CWE-367Published · Updated

Key facts

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

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00395 33rd percentileScored 2026-11-07
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
hfiref0xLightFTPup to 2.3.1—No fix listedCNA
  • LightFTP Vendorhfiref0x Affected up to 2.3.1 Fixed in — No fix listed CNA

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-67607
  2. 2026-10-03 Alias added: GHSA-857x-mm78-cq2m

References

Other 1

  • TI-2026-49347 LightFTP 2.4 Data Race Condition via ABOR Command in ftpserv.c CVSS 4.0HIGH 8.2
  • TI-2023-09823 A race condition in LightFTP through 2.2 allows an attacker to achieve path traversal via… CVSS 3.1HIGH 7.5
  • TI-2025-40345 A buffer overflow in the g_cfg.MaxUsers component of LightFTP v2.0 allows attackers to… CVSS 3.1MEDIUM 6.5
  • TI-2017-14535 LightFTP version 1.1 is vulnerable to a buffer overflow in the "writelogentry" function… CVSS 3.0CRITICAL 9.8

Sources

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