8.3
HIGH CVSS 4.0
CVE-2026-123534
Tornado before 6.6 Path Traversal via static_url() Version Hashing
Description

Tornado before 6.6 contains a path traversal vulnerability in RequestHandler.static_url() and get_version() that allows attackers to hash files outside static_path using ../ sequences. Attackers controlling input passed to static_url() can obtain SHA-512 hashes of readable files to confirm their existence, or reference /dev/zero to block the event loop indefinitely.

INFO

Published Date :

Nov. 8, 2026, 2:16 a.m.

Last Modified :

Nov. 8, 2026, 2:16 a.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-123534 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Tornadoweb tornado
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 3.1 MEDIUM MITRE-CVE
CVSS 3.1 MEDIUM [email protected]
CVSS 4.0 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 HIGH [email protected]
Solution
Update Tornado to version 6.6 or later to fix path traversal and denial of service vulnerabilities.
  • Update Tornado to version 6.6 or later.
  • Sanitize all inputs to static_url() and get_version().
  • Restrict access to static files.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-123534.

URL Resource
https://github.com/tornadoweb/tornado/security/advisories/GHSA-v8g8-cp5j-42fg
https://www.vulncheck.com/advisories/tornado-before-6.6-path-traversal-via-static-url-version-hashing
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-123534 is associated with the following CWEs:

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-123534 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-123534 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Nov. 08, 2026

    Action Type Old Value New Value
    Added Description Tornado before 6.6 contains a path traversal vulnerability in RequestHandler.static_url() and get_version() that allows attackers to hash files outside static_path using ../ sequences. Attackers controlling input passed to static_url() can obtain SHA-512 hashes of readable files to confirm their existence, or reference /dev/zero to block the event loop indefinitely.
    Added CVSS V4.0 AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/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
    Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H
    Added CWE CWE-22
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/123xxx/CVE-2026-123534.json">CVE-2026-123534</a>
    Added Reference https://github.com/tornadoweb/tornado/security/advisories/GHSA-v8g8-cp5j-42fg
    Added Reference https://www.vulncheck.com/advisories/tornado-before-6.6-path-traversal-via-static-url-version-hashing
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.