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TI-2026-22015 Aliases CVE-2026-27633

TinyWeb has Unbounded Content-Length Memory Exhaustion (DoS)

Priority LOW 38CWE-400Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-400.

Summary

TinyWeb is a web server (HTTP, HTTPS) written in Delphi for Win32. Versions prior to version 2.02 have a Denial of Service (DoS) vulnerability via memory exhaustion. Unauthenticated remote attackers can send an HTTP POST request to the server with an exceptionally large `Content-Length` header (e.g., `2147483647`). The server continuously allocates memory for the request body (`EntityBody`) while streaming the payload without enforcing any maximum limit, leading to all available memory being consumed and causing the server to crash. Anyone hosting services using TinyWeb is impacted. Version 2.02 fixes the issue. The patch introduces a `CMaxEntityBodySize` limit (set to 10MB) for the maximum size of accepted payloads. As a temporary workaround if upgrading is not immediately possible, consider placing the server behind a Web Application Firewall (WAF) or reverse proxy (like nginx or Cloudflare) configured to explicitly limit the maximum allowed HTTP request body size (e.g., `client_max_body_size` in nginx).

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00507 43rd percentileScored 2026-11-07
Fix Fixed TinyWeb (maximmasiutin): 2.02

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
maximmasiutinTinyWebbefore 2.022.02Patch availableCNA
  • TinyWeb Vendormaximmasiutin Affected before 2.02 Fixed in 2.02 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:ritlabs:tinyweb:*:*:*:*:*:*:*:*before 2.02Vulnerablemaximmasiutin
  • cpe:2.3:a:ritlabs:tinyweb:*:*:*:*:*:*:*:* Versions before 2.02 Vulnerable ·maximmasiutin

Remediation

  • Fix · CNA TinyWeb (maximmasiutin) Fixed in 2.02

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-27633
  2. 2026-10-25 EPSS moved to the below the 50th percentile

References

Patch 1

Advisory 2

  • TI-2024-04819 Ritlabs TinyWeb Server Request crlf injection CVSS 4.0MEDIUM 6.9
  • TI-2026-18299 TinyWeb CGI Command Injection CVSS 4.0CRITICAL 10.0
  • TI-2026-21999 CGI Parameter Injection (Bypass of STRICT_CGI_PARAMS and EscapeShellParam) CVSS 4.0CRITICAL 10.0
  • TI-2026-22760 TinyWeb: Integer Overflow in `_Val` (HTTP Request Smuggling) CVSS 4.0CRITICAL 9.3
  • TI-2026-23191 TinyWeb: HTTP Header Control Character Injection into CGI Environment CVSS 4.0CRITICAL 9.2
  • TI-2024-22622 TinyWeb 1.94 and below allows unauthenticated remote attackers to cause a denial of… CVSS 3.1HIGH 8.6
See all 7 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences