Vulnerability in Litespeedtech Lsquic

CVE-2025-24947

A hash collision vulnerability (in the hash table used to manage connections) in LSQUIC (aka LiteSpeed QUIC) before 4.2.0 allows remote attackers to cause a considerable CPU load on the server (a Hash DoS attack) by initiating connections with colliding Source Connection IDs (SCIDs). This is caused by XXH32 usage.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.

EPSS exploit prediction

EPSS: 0.007 (50.4th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 50th percentile — 50.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2025-24947: held from 0.007 to 0.007.

EPSS over last 30 days · oldest: 0.007 · newest: 0.007 · change: +0.000

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2025-24947?
CVE-2025-24947 is a medium-severity vulnerability in Litespeedtech Lsquic, classified under Inefficient Algorithmic Complexity. CVSS score: 5.3/10. Published 2025-02-20.
How severe is CVE-2025-24947?
Medium severity. CVSS v3 base score is 5.3 out of 10.
Is CVE-2025-24947 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.