PT-2026-49119 · Tornado · Tornado

CVE-2026-49855 · Published 2026-06-13 · Updated 2026-07-27

Positive Technologies (AI Summary)

CVSS v3.1

7.5

High

Base vector

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

Name of the Vulnerable Software and Affected Versions Tornado versions prior to 6.5.6

Description Gzip decompression routines process data in limited-size chunks but lack an overall limit for the total size of accumulated decompressed chunks. This allows a malicious server to consume unlimited memory when accessed via 'SimpleAsyncHTTPClient' in its default configuration. While 'HTTPServer' is not affected by default, it becomes vulnerable if decompress request=True is set.

Recommendations Update to version 6.5.6 or later. As a temporary workaround, set decompress response=False or use 'CurlAsyncHTTPClient'.

Exploit

Fix

Weakness Enumeration

CWE-409

Related Identifiers

CVE-2026-49855

ECHO-7775-EB27-2601

GHSA-MGF9-4VPG-HJ56

OESA-2026-2727

OESA-2026-2728

OPENSUSE-SU-2026:11027-1

OPENSUSE-SU-2026:21067-1

PYSEC-2026-3389

SUSE-SU-2026:22286-1

SUSE-SU-2026:22373-1

SUSE-SU-2026:22430-1

SUSE-SU-2026:22445-1

SUSE-SU-2026:2725-1

SUSE-SU-2026:2726-1

SUSE-SU-2026:3291-1

Affected Products

Tornado

References · 46

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/49xxx/CVE-2026-49855.json · Exploit
• https://osv.dev/vulnerability/PYSEC-2026-3389 · Vendor Advisory
• https://osv.dev/vulnerability/openSUSE-SU-2026:21067-1 · Vendor Advisory
• https://osv.dev/vulnerability/SUSE-SU-2026:3291-1 · Vendor Advisory
• https://osv.dev/vulnerability/SUSE-SU-2026:22430-1 · Vendor Advisory
• https://osv.dev/vulnerability/DEBIAN-CVE-2026-49855 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-49853 · Security Note
• https://osv.dev/vulnerability/OESA-2026-2728 · Vendor Advisory
• https://osv.dev/vulnerability/GHSA-mgf9-4vpg-hj56 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-49855 · Vendor Advisory
• https://osv.dev/vulnerability/SUSE-SU-2026:2726-1 · Vendor Advisory
• https://osv.dev/vulnerability/UBUNTU-CVE-2026-49855 · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2026-49855 · Security Note
• https://security-tracker.debian.org/tracker/CVE-2026-49855 · Vendor Advisory
• https://osv.dev/vulnerability/SUSE-SU-2026:22286-1 · Vendor Advisory