Tornado: Quadratic DoS via Repeated Header Coalescing

Summary The HTTPHeaders.add method in Tornado accumulates values using string concatenation when the same header name is repeated. Due to Python string immutability, each concatenation copies the entire string, resulting in On² time complexity. Given Tornado's single event loop architecture, a...

GHSA-C98P-7WGM-6P64 Tornado: Quadratic DoS via Repeated Header Coalescing

Summary The HTTPHeaders.add method in Tornado accumulates values using string concatenation when the same header name is repeated. Due to Python string immutability, each concatenation copies the entire string, resulting in On² time complexity. Given Tornado's single event loop architecture, a...

MGASA-2026-0092 Updated python-tornado packages fix security vulnerabilities

Tornado vulnerable to Header Injection and XSS via reason argument. CVE-2025-67724 Tornado is Vulnerable to Quadratic DoS via Repeated Header Coalescing. CVE-2025-67725 Tornado is Vulnerable to Quadratic DoS via Crafted Multipart Parameters. CVE-2025-67726...

tornado: Tornado Quadratic DoS via Repeated Header Coalescing

A denial of service flaw has been discovered in the Tornado networking library. In Tornado, 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...

tornado: Tornado Quadratic DoS via Repeated Header Coalescing

A denial of service flaw has been discovered in the Tornado networking library. In Tornado, 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...

tornado: Tornado Quadratic DoS via Repeated Header Coalescing

A denial of service flaw has been discovered in the Tornado networking library. In Tornado, 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...

AlmaLinux 8 : pcs (ALSA-2026:0930)

The remote AlmaLinux 8 host has packages installed that are affected by multiple vulnerabilities as referenced in the ALSA-2026:0930 advisory. tornado: Tornado Quadratic DoS via Repeated Header Coalescing CVE-2025-67725 tornado: Tornado Quadratic DoS via Crafted Multipart Parameters CVE-2025-6772...

RLSA-2026:0930 Moderate: pcs security update

The pcs packages provide a command-line configuration system for the Pacemaker and Corosync utilities. Security Fixes: tornado: Tornado Quadratic DoS via Repeated Header Coalescing CVE-2025-67725 tornado: Tornado Quadratic DoS via Crafted Multipart Parameters CVE-2025-67726 For more details about...

ALSA-2026:0930 Moderate: pcs security update

The pcs packages provide a command-line configuration system for the Pacemaker and Corosync utilities. Security Fixes: tornado: Tornado Quadratic DoS via Repeated Header Coalescing CVE-2025-67725 tornado: Tornado Quadratic DoS via Crafted Multipart Parameters CVE-2025-67726 For more details about...

Moderate: pcs security update

The pcs packages provide a command-line configuration system for the Pacemaker and Corosync utilities. Security Fixes: tornado: Tornado Quadratic DoS via Repeated Header Coalescing CVE-2025-67725 tornado: Tornado Quadratic DoS via Crafted Multipart Parameters CVE-2025-67726 For more details about...

CVE-2025-67725 Tornado is Vulnerable to Quadratic DoS via Repeated Header Coalescing

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...

CVE-2025-67725

Tornado (Python) vulnerable in versions

CVE-2025-67725 Tornado is Vulnerable to Quadratic DoS via Repeated Header Coalescing

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...