CVE-2026-70637 LightFTP 2.4 Data Race Condition via ABOR Command in ftpserv.c
Anonymous attackers can cause denial of service in LightFTP by exploiting a data race condition between LIST and ABOR commands.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-70637?
CVE-2026-70637 is a high-severity vulnerability in hfiref0x LightFTP, published on 6 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Weakness: CWE-820
Which versions are affected by CVE-2026-70637?
How do I fix CVE-2026-70637?
No fix has been published for CVE-2026-70637 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-70637 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-70637 exists.
Sources
Also known as GHSA-6269-2q48-xxqm.