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.
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Fri, 02 Oct 2026 20:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | 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. | |
| Title | Multidict: Reference leak in CIMultiDict/MultiDict items-view union and subtraction | |
| Weaknesses | CWE-401 | |
| References |
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cvssV3_1
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Status: PUBLISHED
Assigner: GitHub_M
Published:
Updated: 2026-10-02T20:21:50.903Z
Reserved: 2026-10-02T14:59:11.775Z
Link: CVE-2026-104874
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Status : Received
Published: 2026-10-02T21:16:54.993
Modified: 2026-10-02T21:16:54.993
Link: CVE-2026-104874
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OpenCVE Enrichment
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Weaknesses