Tornado: Authorization header forwarded across cross-origin redirects in SimpleAsyncHTTPClient
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
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
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| tornadoweb | tornado | before 6.5.6 | 6.5.6 | Patch available | CNA |
| — | tornado (PyPI) | before 6.5.6 | 6.5.6 | Patch available | GHSA-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.
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| 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 Importantpython-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 Importantpython-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 Importantpython-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 Importantpython-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 Importantpython-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 →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 9 | Affected | No 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
- 2026-10-02 Threatist record created from CVE-2026-49853
- 2026-10-03 Alias added: GHSA-3x9g-8vmp-wqvf
- 2026-10-12 Fix available: RHSA-2026:80741 · Red Hat
- 2026-10-12 Fix available: Red Hat Enterprise Linux AppStream EUS (v. 10.0) · Red Hat
- 2026-10-13 Affected versions changed · Red Hat
- 2026-10-27 Fix available: Red Hat Enterprise Linux AppStream EUS (v.9.6) · Red Hat
- 2026-10-27 Fix available: Red Hat Enterprise Linux AppStream E4S (v.9.4) · Red Hat
- 2026-10-29 Fix available: RHSA-2026:90777 · Red Hat
- 2026-10-29 Fix available: RHSA-2026:90283 · Red Hat
References
Other 5
- https://github.com/tornadoweb/tornado/security/advisories/GHSA-3x9g-8vmp-wqvf
- https://github.com/tornadoweb/tornado/pull/3626
- https://github.com/tornadoweb/tornado/commit/aba2569f7ed7a6bdbef816658fb6b7182531b751
- https://github.com/tornadoweb/tornado/releases/tag/v6.5.6
- https://github.com/tornadoweb/tornado
More tornadoweb vulnerabilities
- 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
Sources
- CVE-2026-49853 · CVE Program
- CVE-2026-49853 · NVD
- FIRST EPSS
- GHSA-3x9g-8vmp-wqvf · GitHub Advisory Database · CC BY 4.0
- CVE-2026-49853 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences