Medium (6.5). EPSS 2.5% chance of exploitation in the next 30 days.
The parse function in llhttp < 2.1.4 and < 6.0.6. ignores chunk extensions when parsing the body of chunked requests. This leads to HTTP Request Smuggling (HRS) under certain conditions.
Severity
CVSS 3.1
6.5 medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
EPSS
2.5% chance of exploitation in the next 30 days; higher than 84% of CVEs (scores of 2026-10-31)