CVE-2026-29046CWE-114CWE-20CWE-74CWE-93

TinyWeb: HTTP Header Control Character Injection into CGI Environment

Critical · published March 6, 2026

CVSS v4.0
9.2
EPSS
0%
Percentile
31.8
In the wild
Unconfirmed
What it is

TinyWeb is a web server (HTTP, HTTPS) written in Delphi for Win32. Prior to version 2.04, TinyWeb accepts request header values and later maps them into CGI environment variables (HTTP_*). The parser did not strictly reject dangerous control characters in header lines and header values, including CR, LF, and NUL, and did not consistently defend against encoded forms such as %0d, %0a, and %00. This can enable header value confusion across parser boundaries and may create unsafe data in the CGI execution context. This issue has been patched in version 2.04.

The record
Technical detail
CVSS v4.0
9.2 · CRITICAL
Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:L/SC:N/SI:H/SA:L
EPSS
0.00387 · 31.8th percentile
Weaknesses
CWE-114 · Process Control; CWE-20 · Improper Input Validation; CWE-74 · Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection'); CWE-93 · Improper Neutralization of CRLF Sequences ('CRLF Injection')
Published
2026-03-06T02:54Z
EPSS history
Timeline
  • 06 MAR 02:54Z
    TinyWeb: HTTP Header Control Character Injection into CGI Environment
    cvelistv5