Security update for python-tornado6 SUSE Patch security@suse.de SUSE Security Team SUSE-SU-2026:0010-1 Final 1 1 2026-01-05T10:26:32Z current 2026-01-05T10:26:32Z 2026-01-05T10:26:32Z cve-database/bin/generate-cvrf.pl 2017-02-24T01:00:00Z Security update for python-tornado6 This update for python-tornado6 fixes the following issues: - CVE-2025-67724: unescaped `reason` argument used in HTTP headers and in HTML default error pages can be used by attackers to launch header injection or XSS attacks (bsc#1254903). - CVE-2025-67725: quadratic complexity of string concatenation operations used by the `HTTPHeaders.add` method can lead to DoS when processing a maliciously crafted HTTP request (bsc#1254905). - CVE-2025-67726: quadratic complexity algorithm used in the `_parseparam` function of `httputil.py` can lead to DoS when processing maliciously crafted parameters in a `Content-Disposition` header (bsc#1254904). The CVRF data is provided by SUSE under the Creative Commons License 4.0 with Attribution (CC-BY-4.0). SUSE-2026-10,SUSE-SLE-Module-Python3-15-SP7-2026-10,SUSE-SLE-Product-HPC-15-SP4-ESPOS-2026-10,SUSE-SLE-Product-HPC-15-SP4-LTSS-2026-10,SUSE-SLE-Product-HPC-15-SP5-ESPOS-2026-10,SUSE-SLE-Product-HPC-15-SP5-LTSS-2026-10,SUSE-SLE-Product-SLES-15-SP4-LTSS-2026-10,SUSE-SLE-Product-SLES-15-SP5-LTSS-2026-10,SUSE-SLE-Product-SLES-15-SP6-LTSS-2026-10,SUSE-SLE-Product-SLES_SAP-15-SP4-2026-10,SUSE-SLE-Product-SLES_SAP-15-SP5-2026-10,SUSE-SLE-Product-SLES_SAP-15-SP6-2026-10,openSUSE-SLE-15.6-2026-10 Copyright SUSE LLC under the Creative Commons License 4.0 with Attribution (CC-BY-4.0) https://www.suse.com/support/update/announcement/2026/suse-su-20260010-1/ Link for SUSE-SU-2026:0010-1 https://lists.suse.com/pipermail/sle-security-updates/2026-January/023678.html E-Mail link for SUSE-SU-2026:0010-1 https://www.suse.com/support/security/rating/ SUSE Security Ratings https://bugzilla.suse.com/1254903 SUSE Bug 1254903 https://bugzilla.suse.com/1254904 SUSE Bug 1254904 https://bugzilla.suse.com/1254905 SUSE Bug 1254905 https://www.suse.com/security/cve/CVE-2025-67724/ SUSE CVE CVE-2025-67724 page https://www.suse.com/security/cve/CVE-2025-67725/ SUSE CVE CVE-2025-67725 page https://www.suse.com/security/cve/CVE-2025-67726/ SUSE CVE CVE-2025-67726 page SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS SUSE Linux Enterprise Module for Python 3 15 SP7 SUSE Linux Enterprise Server 15 SP4-LTSS SUSE Linux Enterprise Server 15 SP5-LTSS SUSE Linux Enterprise Server 15 SP6-LTSS SUSE Linux Enterprise Server for SAP Applications 15 SP4 SUSE Linux Enterprise Server for SAP Applications 15 SP5 SUSE Linux Enterprise Server for SAP Applications 15 SP6 openSUSE Leap 15.6 python311-tornado6-6.3.2-150400.9.12.1 python311-tornado6-6.3.2-150400.9.12.1 as a component of SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS python311-tornado6-6.3.2-150400.9.12.1 as a component of SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS python311-tornado6-6.3.2-150400.9.12.1 as a component of SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS python311-tornado6-6.3.2-150400.9.12.1 as a component of SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS python311-tornado6-6.3.2-150400.9.12.1 as a component of SUSE Linux Enterprise Module for Python 3 15 SP7 python311-tornado6-6.3.2-150400.9.12.1 as a component of SUSE Linux Enterprise Server 15 SP4-LTSS python311-tornado6-6.3.2-150400.9.12.1 as a component of SUSE Linux Enterprise Server 15 SP5-LTSS python311-tornado6-6.3.2-150400.9.12.1 as a component of SUSE Linux Enterprise Server 15 SP6-LTSS python311-tornado6-6.3.2-150400.9.12.1 as a component of SUSE Linux Enterprise Server for SAP Applications 15 SP4 python311-tornado6-6.3.2-150400.9.12.1 as a component of SUSE Linux Enterprise Server for SAP Applications 15 SP5 python311-tornado6-6.3.2-150400.9.12.1 as a component of SUSE Linux Enterprise Server for SAP Applications 15 SP6 python311-tornado6-6.3.2-150400.9.12.1 as a component of openSUSE Leap 15.6 Tornado is a Python web framework and asynchronous networking library. In versions 6.5.2 and below, the supplied reason phrase is used unescaped in HTTP headers (where it could be used for header injection) or in HTML in the default error page (where it could be used for XSS) and can be exploited by passing untrusted or malicious data into the reason argument. Used by both RequestHandler.set_status and tornado.web.HTTPError, the argument is designed to allow applications to pass custom "reason" phrases (the "Not Found" in HTTP/1.1 404 Not Found) to the HTTP status line (mainly for non-standard status codes). This issue is fixed in version 6.5.3. CVE-2025-67724 SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise Module for Python 3 15 SP7:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise Server 15 SP4-LTSS:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise Server 15 SP5-LTSS:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise Server 15 SP6-LTSS:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise Server for SAP Applications 15 SP4:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise Server for SAP Applications 15 SP5:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise Server for SAP Applications 15 SP6:python311-tornado6-6.3.2-150400.9.12.1 openSUSE Leap 15.6:python311-tornado6-6.3.2-150400.9.12.1 important To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch". https://www.suse.com/support/update/announcement/2026/suse-su-20260010-1/ https://www.suse.com/security/cve/CVE-2025-67724.html CVE-2025-67724 https://bugzilla.suse.com/1254903 SUSE Bug 1254903 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(n^2) 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 SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise Module for Python 3 15 SP7:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise Server 15 SP4-LTSS:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise Server 15 SP5-LTSS:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise Server 15 SP6-LTSS:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise Server for SAP Applications 15 SP4:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise Server for SAP Applications 15 SP5:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise Server for SAP Applications 15 SP6:python311-tornado6-6.3.2-150400.9.12.1 openSUSE Leap 15.6:python311-tornado6-6.3.2-150400.9.12.1 important To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch". https://www.suse.com/support/update/announcement/2026/suse-su-20260010-1/ https://www.suse.com/security/cve/CVE-2025-67725.html CVE-2025-67725 https://bugzilla.suse.com/1254905 SUSE Bug 1254905 Tornado is a Python web framework and asynchronous networking library. Versions 6.5.2 and below use an inefficient algorithm when parsing parameters for HTTP header values, potentially causing a DoS. The _parseparam function in httputil.py is used to parse specific HTTP header values, such as those in multipart/form-data and repeatedly calls string.count() within a nested loop while processing quoted semicolons. If an attacker sends a request with a large number of maliciously crafted parameters in a Content-Disposition header, the server's CPU usage increases quadratically (O(n^2)) during parsing. Due to Tornado's single event loop architecture, a single malicious request can cause the entire server to become unresponsive for an extended period. This issue is fixed in version 6.5.3. CVE-2025-67726 SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise Module for Python 3 15 SP7:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise Server 15 SP4-LTSS:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise Server 15 SP5-LTSS:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise Server 15 SP6-LTSS:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise Server for SAP Applications 15 SP4:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise Server for SAP Applications 15 SP5:python311-tornado6-6.3.2-150400.9.12.1 SUSE Linux Enterprise Server for SAP Applications 15 SP6:python311-tornado6-6.3.2-150400.9.12.1 openSUSE Leap 15.6:python311-tornado6-6.3.2-150400.9.12.1 important To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch". https://www.suse.com/support/update/announcement/2026/suse-su-20260010-1/ https://www.suse.com/security/cve/CVE-2025-67726.html CVE-2025-67726 https://bugzilla.suse.com/1254904 SUSE Bug 1254904