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CVE

CVE-2025-12642

lighttpd1.4.80 incorrectly merged trailer fields into headers after http request parsing.
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CVE

CVE-2025-12642

lighttpd1.4.80 incorrectly merged trailer fields into headers after http request parsing.

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

Package Versions Affected

Package Version
patch Availability
No items found.

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CVSS Version

Severity
Base Score
CVSS Version
Score Vector
C
H
U
6.9
-
4.0
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
C
H
U
0
-
3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
C
H
U
-

Related Resources

No items found.

References

https://github.com/lighttpd/lighttpd1.4/commit/35cb89c103877de62d6b63d0804255475d77e5e1

Severity

9.1

CVSS Score
0
10

Basic Information

Ecosystem
Base CVSS
9.1
EPSS Probability
0.00059%
EPSS Percentile
0.18787%
Introduced Version
0
Fix Available
35cb89c103877de62d6b63d0804255475d77e5e1

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