Vulnerability in Hiawatha Web Server

CVE-2025-57783

Improper header parsing may lead to request smuggling has been identified in Hiawatha webserver version 11.7 which allows an unauthenticated attacker to access restricted resources managed by Hiawatha webserver.

EPSS: 0.004 (36.7th percentile) — read the EPSS interpretation.

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:L/I:N/A:N.

Affected products

References

Frequently asked questions

What is CVE-2025-57783?
CVE-2025-57783 is a medium-severity vulnerability in Hiawatha Web Server, classified under CWE-444 INCONSISTENT INTERPRETATION OF HTTP REQUESTS ('HTTP REQUEST SMUGGLING'). CVSS score: 5.3/10. Published 2026-01-26.
How severe is CVE-2025-57783?
Medium severity. CVSS v3 base score is 5.3 out of 10.