Vulnerability · Published Jan 26, 2026 · Assigned by certcc
CVE-2025-57783Improper header parsing may lead to request smuggling
Medium 5.3
In plain English
A medium-severity security flaw in Hiawatha Web server from Hiawatha. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 41% of all known vulnerabilities).
Severity (CVSS 3.1)5.3Medium
Exploit odds (30 days)0.5%top 59.0% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
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.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Hiawatha | Hiawatha Web server | 11.7 – through 8.5 |