CVE-2025-12642 — HTTP Request Smuggling in Lighttpd
Severity
6.9MEDIUMNVD
EPSS
0.1%
top 80.09%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
Timeline
PublishedNov 3
Description
lighttpd1.4.80 incorrectly merged trailer fields into headers after http request parsing. This behavior can be exploited to conduct HTTP Header Smuggling attacks.
Successful exploitation may allow an attacker to:
* Bypass access control rules
* Inject unsafe input into backend logic that trusts request headers
* Execute HTTP Request Smuggling attacks under some conditions
This issue affects lighttpd1.4.80
CVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N