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TI-2026-65637 Aliases CVE-2026-103262GHSA-h36x-fm6v-f9vx

Tornado before 6.5.9 Denial of Service via CurlAsyncHTTPClient

Priority HIGH 77CWE-409Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
—
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 9 fixed, 7 without a fix

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat.

Summary

Tornado versions before 6.5.9 contain an unbounded memory accumulation vulnerability in CurlAsyncHTTPClient that allows remote attackers to cause denial of service by sending a compressed response. Attackers can send a gzip-encoded decompression bomb that accumulates in memory without size limits, causing the application process to be killed by out-of-memory conditions.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00628 50th percentileScored 2026-11-07
Fix Partial tornado (tornadoweb): 6.5.9Red Hat: 9 advisoriesRed Hat: 9 fixed, 7 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
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 6.5.96.5.9Patch availableCNA
  • tornado Vendortornadoweb Affected before 6.5.9 Fixed in 6.5.9 Patch available CNA

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 6.5.9

Red Hat 9 advisories

  • RHSA-2026:91583 Released 2026-10-28 · Red Hat rating Important
    python-tornado security update
    • Red Hat Enterprise Linux AppStream EUS (v. 10.0) python-tornado-6.5.10-0.el10_0.1, python3-tornado-6.5.10-0.el10_0.1
  • RHSA-2026:89197 Released 2026-10-27 · Red Hat rating Critical
    OpenShift Container Platform 4.22.20 bug fix and security update
    • Red Hat OpenShift Container Platform 4.22 rhcos-aarch64-4.22.9.8.202610241758-0, rhcos-ppc64le-4.22.9.8.202610241758-0, rhcos-s390x-4.22.9.8.202610241758-0 +1
  • 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
Show 6 more Red Hat advisories
  • RHSA-2026:87410 Released 2026-10-21 · Red Hat rating Critical
    RHOAI 2.25.12 - Red Hat OpenShift AI
    • Red Hat OpenShift AI 2.25 registry.redhat.io/rhoai/odh-built-in-detector-rhel9, registry.redhat.io/rhoai/odh-caikit-nlp-rhel9, registry.redhat.io/rhoai/odh-codeflare-operator-rhel9 +47
  • RHSA-2026:87124 Released 2026-10-21 · Red Hat rating Critical
    Red Hat Ansible Automation Platform 2.7 Container Release Update
    • Red Hat Ansible Automation Platform 2.7 registry.redhat.io/ansible-automation-platform-27/de-supported-rhel9, registry.redhat.io/ansible-automation-platform-27/eda-controller-rhel9, registry.redhat.io/ansible-automation-platform-27/ee-supported-rhel9 +8
  • RHSA-2026:87120 Released 2026-10-21 · Red Hat rating Critical
    Red Hat Ansible Automation Platform 2.6 Container Release Update
    • Red Hat Ansible Automation Platform 2.6 registry.redhat.io/ansible-automation-platform-26/eda-controller-rhel9, registry.redhat.io/ansible-automation-platform-26/ee-supported-rhel9, registry.redhat.io/ansible-automation-platform-26/gateway-rhel9 +8
  • RHSA-2026:84734 Released 2026-10-19 · Red Hat rating Critical
    RHOAI 3.4.5 - Red Hat OpenShift AI
    • Red Hat OpenShift AI 3.4 registry.redhat.io/rhoai/odh-ai-gateway-payload-processing-rhel9, registry.redhat.io/rhoai/odh-automl-rhel9, registry.redhat.io/rhoai/odh-autorag-rhel9 +47
  • RHSA-2026:82040 Released 2026-10-13 · Red Hat rating Important
    python-tornado security update
    • Red Hat Enterprise Linux AppStream (v. 9) python-tornado-6.5.10-1.el9_8.1, python3-tornado-6.5.10-1.el9_8.1
  • RHSA-2026:82041 Released 2026-10-13 · Red Hat rating Important
    python-tornado security update
    • Red Hat Enterprise Linux AppStream (v. 10) python-tornado-6.5.10-1.el10_2.1, python3-tornado-6.5.10-1.el10_2.1

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    tornadoweb tornado 6.5.9

    3 records Highest priority Priority HIGH 2 HIGH, 1 LOW

    Other records, highest priority first

    • TI-2026-65638 Tornado before 6.5.9 StaticFileHandler Path Traversal via SymlinkPriority HIGH 69
    • TI-2026-65636 Tornado before 6.5.9 Denial of Service via Query StringPriority LOW 37
    Show all 3 records →

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Lightspeed CoreAffectedNo fix yet
OpenShift LightspeedAffectedNo fix planned: Will not fix
Red Hat Enterprise Linux AI (RHEL AI) 3AffectedNo fix yet
Red Hat OpenShift AI (RHOAI)AffectedNo fix yet
Red Hat OpenShift Container Platform 5AffectedNo fix yet
Red Hat OpenStack Platform 16.2AffectedNo fix yet
Red Hat OpenStack Platform 17.1AffectedNo fix yet
Red Hat Ansible Automation Platform 2.6Fixed RHSA-2026:87120
Red Hat Ansible Automation Platform 2.7Fixed RHSA-2026:87124
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:82041
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:82040
Red Hat Enterprise Linux AppStream EUS (v. 10.0)Fixed RHSA-2026:91583
Red Hat Enterprise Linux AppStream EUS (v.9.6)Fixed RHSA-2026:90283
Red Hat OpenShift AI 2.25Fixed RHSA-2026:87410
Red Hat OpenShift AI 3.4Fixed RHSA-2026:84734
Red Hat OpenShift Container Platform 4.22Fixed RHSA-2026:89197
Not affected: 8 products
  • Migration Toolkit for Applications 8
  • Red Hat Ansible Automation Platform 2.6
  • Red Hat Ansible Automation Platform 2.7
  • Red Hat Enterprise Linux 8
  • Red Hat OpenShift AI (RHOAI)
  • Red Hat OpenShift AI 2.25
  • Red Hat OpenShift AI 3.4
  • Red Hat OpenShift Container Platform 4

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-103262
  2. 2026-10-03 Alias added: GHSA-h36x-fm6v-f9vx
  3. 2026-10-06 CISA SSVC decision points changed
  4. 2026-10-06 Priority changed: LOW → HIGH
  5. 2026-10-13 Fix available: RHSA-2026:82041 · Red Hat
  6. 2026-10-13 Fix available: RHSA-2026:82040 · Red Hat
  7. 2026-10-13 Fix available: Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux AppStream (v. 9) · Red Hat
  8. 2026-10-16 Affected versions changed · Red Hat
  9. 2026-10-18 Affected versions changed · Red Hat
  10. 2026-10-20 Fix available: RHSA-2026:84734 · Red Hat
  11. 2026-10-20 Fix available: Red Hat OpenShift AI 3.4 · Red Hat
  12. 2026-10-22 Fix available: RHSA-2026:87124 · Red Hat
  13. 2026-10-22 Fix available: RHSA-2026:87120 · Red Hat
  14. 2026-10-22 Fix available: RHSA-2026:87410 · Red Hat
  15. 2026-10-23 Fix available: Red Hat Ansible Automation Platform 2.6, Red Hat Ansible Automation Platform 2.7, Red Hat OpenShift AI 2.25 · Red Hat
  16. 2026-10-27 Fix available: Red Hat Enterprise Linux AppStream EUS (v.9.6) · Red Hat
  17. 2026-10-28 Fix available: Red Hat OpenShift Container Platform 4.22 · Red Hat
  18. 2026-10-29 EPSS moved to the 50th–90th percentile
  19. 2026-10-29 Fix available: Red Hat Enterprise Linux AppStream EUS (v. 10.0) · Red Hat
  20. 2026-10-29 Fix available: RHSA-2026:90283 · Red Hat
  21. 2026-10-29 Fix available: RHSA-2026:91583 · Red Hat
  22. 2026-10-29 Fix available: RHSA-2026:89197 · Red Hat
  23. 2026-10-30 Affected versions changed · Red Hat

References

Patch 1

Advisory 1

  • 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
  • TI-2026-24502 Tornado has a DoS due to too many multipart parts CVSS 4.0HIGH 8.7
See all 25 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences