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TI-2026-22012 Aliases CVE-2026-27630

TinyWeb vulnerable to Remote Denial of Service via Thread/Connection Exhaustion (Slowloris)

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 are vulnerable to a Denial of Service (DoS) attack known as Slowloris. The server spawns a new OS thread for every incoming connection without enforcing a maximum concurrency limit or an appropriate request timeout. An unauthenticated remote attacker can exhaust server concurrency limits and memory by opening numerous connections and sending data exceptionally slowly (e.g. 1 byte every few minutes). Anyone hosting services using TinyWeb is impacted. Version 2.02 fixes the issue. The patch introduces a `CMaxConnections` limit (set to 512) and a `CConnectionTimeoutSecs` idle timeout (set to 30 seconds). As a temporary workaround if upgrading is not immediately possible, consider placing the server behind a robust reverse proxy or Web Application Firewall (WAF) such as nginx, HAProxy, or Cloudflare, configured to buffer incomplete requests and aggressively enforce connection limits and timeouts.

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-2026-27630
  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