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TI-2026-36757 Aliases CVE-2026-49853GHSA-3x9g-8vmp-wqvf

Tornado: Authorization header forwarded across cross-origin redirects in SimpleAsyncHTTPClient

Priority LOW 34CWE-200Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Information disclosure
Confidentiality · integrity · availability
High · None · None
Fix status
Partial Red Hat: 5 fixed, 1 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-200.

Summary

Tornado is a Python web framework and asynchronous networking library. Prior to 6.5.6, SimpleAsyncHTTPClient shallow-copied redirected requests and removed only the Host header, leaving Authorization, auth_username, auth_password, and auth_mode in place when a redirect changed scheme, host, or port. This issue is fixed in version 6.5.6.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00445 38th percentileScored 2026-11-07
Fix Partial tornado (tornadoweb): 6.5.6tornado (PyPI): 6.5.6Red Hat: 5 advisoriesRed Hat: 5 fixed, 1 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
tornadowebtornadobefore 6.5.66.5.6Patch availableCNA
—tornado (PyPI)before 6.5.66.5.6Patch availableGHSA-3x9g-8vmp-wqvf
  • tornado Vendortornadoweb Affected before 6.5.6 Fixed in 6.5.6 Patch available CNA
  • tornado (PyPI) Vendor— Affected before 6.5.6 Fixed in 6.5.6 Patch available GHSA-3x9g-8vmp-wqvf

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:tornadoweb:tornado:*:*:*:*:*:*:*:*——tornadoweb
  • cpe:2.3:a:tornadoweb:tornado:*:*:*:*:*:*:*:* Versions — — ·tornadoweb

Remediation

  • Fix · CNA tornado (tornadoweb) Fixed in 6.5.6
  • Fix · GHSA-3x9g-8vmp-wqvf tornado (PyPI) Fixed in 6.5.6 Advisory →

Red Hat 5 advisories

  • RHSA-2026:90777 Released 2026-10-27 · Red Hat rating Important
    python-tornado security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.4) python-tornado-6.4.2-1.el9_4.3, python3-tornado-6.4.2-1.el9_4.3
  • RHSA-2026:90283 Released 2026-10-26 · Red Hat rating Important
    python-tornado security update
    • Red Hat Enterprise Linux AppStream EUS (v.9.6) python-tornado-6.4.2-2.el9_6.7, python3-tornado-6.4.2-2.el9_6.7
  • RHSA-2026:80741 Released 2026-10-12 · Red Hat rating Important
    python-tornado security update
    • Red Hat Enterprise Linux AppStream EUS (v. 10.0) python-tornado-6.5.8-0.el10_0.1, python3-tornado-6.5.8-0.el10_0.1
Show 2 more Red Hat advisories
  • RHSA-2026:67146 Released 2026-09-14 · Red Hat rating Important
    python-tornado security update
    • Red Hat Enterprise Linux AppStream (v. 9) python-tornado-6.5.8-0.el9_8.1, python3-tornado-6.5.8-0.el9_8.1
  • RHSA-2026:67147 Released 2026-09-14 · Red Hat rating Important
    python-tornado security update
    • Red Hat Enterprise Linux AppStream (v. 10) python-tornado-6.5.8-0.el10_2.1, python3-tornado-6.5.8-0.el10_2.1

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 9AffectedNo fix yet
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:67147
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:67146
Red Hat Enterprise Linux AppStream E4S (v.9.4)Fixed RHSA-2026:90777
Red Hat Enterprise Linux AppStream EUS (v. 10.0)Fixed RHSA-2026:80741
Red Hat Enterprise Linux AppStream EUS (v.9.6)Fixed RHSA-2026:90283
Not affected: 12 products
  • Exploit Intelligence
  • Lightspeed Core
  • Migration Toolkit for Applications 8
  • OpenShift Lightspeed
  • Red Hat Ansible Automation Platform 2
  • Red Hat Enterprise Linux 10
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux AI (RHEL AI) 3
  • Red Hat Enterprise Linux AppStream E4S (v.9.4)
  • Red Hat OpenShift AI (RHOAI)
  • Red Hat OpenShift Container Platform 4
  • Red Hat OpenStack Platform 16.2

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-49853
  2. 2026-10-03 Alias added: GHSA-3x9g-8vmp-wqvf
  3. 2026-10-12 Fix available: RHSA-2026:80741 · Red Hat
  4. 2026-10-12 Fix available: Red Hat Enterprise Linux AppStream EUS (v. 10.0) · Red Hat
  5. 2026-10-13 Affected versions changed · Red Hat
  6. 2026-10-27 Fix available: Red Hat Enterprise Linux AppStream EUS (v.9.6) · Red Hat
  7. 2026-10-27 Fix available: Red Hat Enterprise Linux AppStream E4S (v.9.4) · Red Hat
  8. 2026-10-29 Fix available: RHSA-2026:90777 · Red Hat
  9. 2026-10-29 Fix available: RHSA-2026:90283 · Red Hat

References

  • TI-2026-65637 Tornado before 6.5.9 Denial of Service via CurlAsyncHTTPClient CVSS 4.0HIGH 8.7
  • TI-2026-62120 Tornado before 6.5.8 Memory Amplification DoS via multipart CVSS 4.0HIGH 8.7
  • TI-2024-13023 Tornado before 6.4.1 HTTP Request Smuggling via Transfer-Encoding CVSS 4.0CRITICAL 9.0
  • TI-2026-65638 Tornado before 6.5.9 StaticFileHandler Path Traversal via Symlink CVSS 4.0HIGH 8.2
  • TI-2026-62122 Tornado before 6.5.7 Credential Leak via Handle Reuse CVSS 4.0HIGH 8.2
  • TI-2026-62121 Tornado before 6.5.8 Cookie Attribute Injection via Capitalized kwargs CVSS 4.0MEDIUM 6.3
See all 27 →

Sources