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TI-2026-66145 Aliases CVE-2026-104874GHSA-54p9-h82j-f925

Multidict: Reference leak in CIMultiDict/MultiDict items-view union and subtraction

Priority MEDIUM 63CWE-401Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · Low
Fix status
Partial Red Hat: 4 fixed, 14 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-401.

Summary

Multidict is an implementation of a multidict data structure. From 6.7.0 until 6.9.1, the C extension's items-view reflected union operation, operand | d.items(), in multidict_itemsview_or2_impl and subtraction operation, d.items() - operand, in multidict_itemsview_sub1_impl fail to release new key-identity and value references returned for each operand element. Applications that perform these operations over attacker-influenced sequences can leak two strong references per element, and garbage collection cannot reclaim them, so repeated operations can cause unbounded process memory growth and denial of service. Forward union, intersection, non-tuple operand elements, and pure-Python builds are not affected by this reference leak. This issue is fixed in version 6.9.1.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00448 39th percentileScored 2026-11-07
Fix Partial multidict (aio-libs): 6.9.1multidict (PyPI): 6.9.1Red Hat: 14 advisoriesRed Hat: 4 fixed, 14 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
aio-libsmultidict6.7.0 to before 6.9.16.9.1Patch availableCNA
—multidict (PyPI)6.7.0 to before 6.9.16.9.1Patch availableGHSA-54p9-h82j-f925
  • multidict Vendoraio-libs Affected 6.7.0 to before 6.9.1 Fixed in 6.9.1 Patch available CNA
  • multidict (PyPI) Vendor— Affected 6.7.0 to before 6.9.1 Fixed in 6.9.1 Patch available GHSA-54p9-h82j-f925

Remediation

  • Fix · CNA multidict (aio-libs) Fixed in 6.9.1
  • Fix · GHSA-54p9-h82j-f925 multidict (PyPI) Fixed in 6.9.1 Advisory →

Red Hat 14 advisories

  • RHSA-2026:92452 Released 2026-10-29 · Red Hat rating Critical
    Red Hat Enterprise Linux AI 3.5.2 enhancement update
    • Red Hat Enterprise Linux AI 3.5 registry.redhat.io/rhelai3/bootc-aws-cuda-rhel9, registry.redhat.io/rhelai3/bootc-azure-cuda-rhel9, registry.redhat.io/rhelai3/bootc-azure-rocm-rhel9 +3
  • RHSA-2026:92449 Released 2026-10-29 · Red Hat rating Critical
    Red Hat Enterprise Linux AI 3.5.2 enhancement update
    • Red Hat Enterprise Linux AI 3.5 registry.redhat.io/rhelai3/disk-image-cuda-rhel9
  • RHSA-2026:90440 Released 2026-10-26 · Red Hat rating Important
    Red Hat Enterprise Linux AI 3.4.6 security update
    • Red Hat Enterprise Linux AI 3.4 registry.redhat.io/rhelai3/bootc-aws-cuda-rhel9, registry.redhat.io/rhelai3/bootc-azure-cuda-rhel9, registry.redhat.io/rhelai3/bootc-azure-rocm-rhel9 +3
Show 11 more Red Hat advisories
  • RHSA-2026:90432 Released 2026-10-26 · Red Hat rating Important
    Red Hat Enterprise Linux AI 3.4.6 security update
    • Red Hat Enterprise Linux AI 3.4 registry.redhat.io/rhelai3/disk-image-cuda-rhel9
  • RHSA-2026:83121 Released 2026-10-14 · Red Hat rating Important
    Red Hat AI Inference 3.4.6 (rocm)
    • Red Hat AI Inference Server 3.4 registry.redhat.io/rhaii/vllm-rocm-rhel9
  • RHSA-2026:83120 Released 2026-10-14 · Red Hat rating Important
    Red Hat AI Inference 3.4.6 (cuda)
    • Red Hat AI Inference Server 3.4 registry.redhat.io/rhaii/vllm-cuda-rhel9
  • RHSA-2026:83116 Released 2026-10-14 · Red Hat rating Important
    Red Hat AI Inference Model Optimization Tools 3.4.6 (cuda)
    • Red Hat AI Inference Server 3.4 registry.redhat.io/rhaii/model-opt-cuda-rhel9
  • RHSA-2026:83114 Released 2026-10-14 · Red Hat rating Important
    Red Hat AI Inference 3.4.6 (spyre)
    • Red Hat AI Inference Server 3.4 registry.redhat.io/rhaii/vllm-spyre-rhel9
  • RHSA-2026:83112 Released 2026-10-14 · Red Hat rating Important
    Red Hat AI Inference 3.4.6 (cpu)
    • Red Hat AI Inference Server 3.4 registry.redhat.io/rhaii/vllm-cpu-rhel9
  • RHSA-2026:82415 Released 2026-10-13 · Red Hat rating Critical
    Red Hat AI Inference 3.5.2 (cpu)
    • Red Hat AI Inference Server 3.5 registry.redhat.io/rhaii/vllm-cpu-rhel9
  • RHSA-2026:82371 Released 2026-10-13 · Red Hat rating Critical
    Red Hat AI Inference 3.5.2 (spyre)
    • Red Hat AI Inference Server 3.5 registry.redhat.io/rhaii/vllm-spyre-rhel9
  • RHSA-2026:82368 Released 2026-10-13 · Red Hat rating Critical
    Red Hat AI Inference 3.5.2 (cuda)
    • Red Hat AI Inference Server 3.5 registry.redhat.io/rhaii/vllm-cuda-rhel9
  • RHSA-2026:82061 Released 2026-10-13 · Red Hat rating Critical
    Red Hat AI Inference Tech Preview 3.5.2 (Gaudi)
    • Red Hat AI Inference Server 3.5 registry.redhat.io/rhaii/vllm-gaudi-rhel9
  • RHSA-2026:82059 Released 2026-10-13 · Red Hat rating Critical
    Red Hat AI Inference 3.5.2 (ROCm)
    • Red Hat AI Inference Server 3.5 registry.redhat.io/rhaii/vllm-rocm-rhel9

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Exploit IntelligenceAffectedNo fix planned: Out of support scope
Lightspeed CoreAffectedNo fix yet: Fix deferred
Migration Toolkit for Applications 8AffectedNo fix yet: Fix deferred
OpenShift LightspeedAffectedNo fix yet: Fix deferred
Red Hat AI Inference ServerAffectedNo fix yet: Fix deferred
Red Hat Ansible Automation Platform 2AffectedNo fix yet: Fix deferred
Red Hat Ansible Automation Platform Ansible Core 2AffectedNo fix yet: Fix deferred
Red Hat Discovery 2AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux AI (RHEL AI) 3AffectedNo fix yet: Fix deferred
Red Hat Lightspeed Services for OCPAffectedNo fix yet: Fix deferred
Red Hat OpenShift AI (RHOAI)AffectedNo fix yet: Fix deferred
Red Hat Satellite 6AffectedNo fix yet: Fix deferred
Red Hat Update Infrastructure 4 for Cloud ProvidersAffectedNo fix planned: Out of support scope
Red Hat Update Infrastructure 5AffectedNo fix yet: Fix deferred
Red Hat AI Inference Server 3.4Fixed RHSA-2026:83112, RHSA-2026:83114, RHSA-2026:83116, RHSA-2026:83120, RHSA-2026:83121
Red Hat AI Inference Server 3.5Fixed RHSA-2026:82059, RHSA-2026:82061, RHSA-2026:82368, RHSA-2026:82371, RHSA-2026:82415
Red Hat Enterprise Linux AI 3.4Fixed RHSA-2026:90432, RHSA-2026:90440
Red Hat Enterprise Linux AI 3.5Fixed RHSA-2026:92449, RHSA-2026:92452
Not affected: 1 product
  • Red Hat Hardened Images

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-104874
  2. 2026-10-05 CISA SSVC decision points changed
  3. 2026-10-05 Priority changed: LOW → MEDIUM
  4. 2026-10-06 Alias added: GHSA-54p9-h82j-f925
  5. 2026-10-06 Fix available: PyPI/[email protected] · GHSA-54p9-h82j-f925
  6. 2026-10-06 CVSS score added · GHSA-54p9-h82j-f925
  7. 2026-10-06 Weakness changed · GHSA-54p9-h82j-f925
  8. 2026-10-06 5 new references · GHSA-54p9-h82j-f925
  9. 2026-10-13 Fix available: RHSA-2026:82061 · Red Hat
  10. 2026-10-13 Fix available: RHSA-2026:82059 · Red Hat
  11. 2026-10-13 Fix available: Red Hat AI Inference Server 3.5 · Red Hat
  12. 2026-10-14 Fix available: RHSA-2026:82368 · Red Hat
  13. 2026-10-14 Fix available: RHSA-2026:82415 · Red Hat
  14. 2026-10-14 Fix available: RHSA-2026:82371 · Red Hat
  15. 2026-10-16 Fix available: RHSA-2026:83112 · Red Hat
  16. 2026-10-16 Fix available: RHSA-2026:83116 · Red Hat
  17. 2026-10-16 Fix available: RHSA-2026:83114 · Red Hat
  18. 2026-10-16 Fix available: RHSA-2026:83120 · Red Hat
  19. 2026-10-16 Fix available: RHSA-2026:83121 · Red Hat
  20. 2026-10-16 Fix available: Red Hat AI Inference Server 3.4 · Red Hat
  21. 2026-10-30 Fix available: RHSA-2026:92452 · Red Hat
  22. 2026-10-30 Fix available: RHSA-2026:92449 · Red Hat
  23. 2026-10-30 Fix available: RHSA-2026:90432 · Red Hat
  24. 2026-10-30 Fix available: RHSA-2026:90440 · Red Hat
  25. 2026-10-30 Fix available: Red Hat Enterprise Linux AI 3.4, Red Hat Enterprise Linux AI 3.5 · Red Hat

References

Advisory 1

Other 4

  • TI-2025-38826 aiomysql allows arbitrary access to client files through vulnerability of a malicious MySQL server CVSS 4.0HIGH 8.2
  • TI-2024-15436 aiohttp.web.static(follow_symlinks=True) is vulnerable to directory traversal CVSS 3.1HIGH 7.5
  • TI-2023-25769 Request smuggling in aiohttp CVSS 3.1HIGH 7.5
  • TI-2023-18906 aiohttp vulnerable to HTTP request smuggling CVSS 3.1HIGH 7.5
  • TI-2023-26746 aiohttp's ClientSession is vulnerable to CRLF injection via version CVSS 3.1HIGH 7.2
  • TI-2023-26747 aiohttp's ClientSession is vulnerable to CRLF injection via method CVSS 3.1MEDIUM 5.3
See all 59 →

Sources

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