Detections
Analytics

Echo: tornado: security update to 6.5.3

high Tenable Cloud Security Plugin ID 460957

Description

There are packages installed that are affected by a vulnerability referenced in the following CVE:

 - Tornado is a Python web framework and asynchronous networking library. In versions 6.5.2 and below, a
 single maliciously crafted HTTP request can block the server's event loop for an extended period, caused
 by the HTTPHeaders.add method. The function accumulates values using string concatenation when the same
 header name is repeated, causing a Denial of Service (DoS). Due to Python string immutability, each
 concatenation copies the entire string, resulting in O(n²) time complexity. The severity can vary from
 high if max_header_size has been increased from its default, to low if it has its default value of 64KB.
 This issue is fixed in version 6.5.3. (CVE-2025-67725)

Solution

Update the tornado library and its related packages to version 6.5.3 or later.

See Also

https://advisory.echohq.com/cve/CVE-2025-67725

Plugin Details

Severity: High

ID: 460957

Version: Revision 1.1

Type: Local

Published: 10/2/2026

Updated: 10/3/2026

Supported Sensors: Tenable Cloud Security, Tenable Self-Hosted Container Security

Risk Information

VPR

Risk Factor: Low

Score: 3

Percentile: 23.38

CVSS v2

Risk Factor: High

Base Score: 7.8

Temporal Score: 5.8

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C

CVSS Score Source: CVE-2025-67725

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

Exploit Ease: No known exploits are available

Patch Publication Date: 8/12/2026

Vulnerability Publication Date: 12/12/2025

Reference Information

CVE: CVE-2025-67725

IAVB: 2026-B-0009-S