CVE-2025-54939 Denial of service in LSQUIC
A memory leak in the LSQUIC library allows attackers to cause a denial of service by exhausting system memory.
- 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-2025-54939?
CVE-2025-54939 is a medium-severity denial of service vulnerability in litespeedtech LSQUIC, published on 1 Aug 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
LiteSpeed QUIC (LSQUIC) Library before 4.3.1 has an lsquic_engine_packet_in memory leak.
Which versions are affected by CVE-2025-54939?
It affects 4 products.
Products include Litespeedtech Litespeed Web Adc, Litespeedtech Litespeed Web Server, Litespeedtech Lsquic, Litespeedtech Openlitespeed.
How do I fix CVE-2025-54939?
No fix has been published for CVE-2025-54939 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2025-54939 being exploited?
There is no known exploitation of CVE-2025-54939 in the wild and no public exploit code.
Public exploit code: 1 proofs of concept on GitHub.
Sources
Also known as GHSA-839r-7hhg-xhqr.