{"id":"CVE-2026-104874","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-104874","generatedAt":"2026-10-28T05:28:07.504Z","title":"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.","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.","published":"2026-10-02T21:16:55.000Z","lastModified":"2026-10-06T16:08:43.000Z","status":"Deferred","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":5.3,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"},"cwe":["CWE-401"],"affected":[],"epss":{"score":0.00448,"percentile":0.38775,"date":"2026-10-27","history":[{"date":"2026-10-03","score":0.00297,"percentile":0.20381}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.45%). Track it; it rarely justifies an emergency change on its own."},"changes":[{"kind":"new","label":"New CVE","at":"2026-10-02T21:16:55.000Z","detail":{"score":"5.3","severity":"MEDIUM","publishedAt":"2026-10-02T21:16:54.993Z"},"summary":"New CVE, medium severity (CVSS 5.3)."}],"references":[{"url":"https://github.com/aio-libs/multidict/commit/350b4a07bf8ff851b6d7544e81b1c748bdc74c40","source":"security-advisories@github.com"},{"url":"https://github.com/aio-libs/multidict/releases/tag/v6.9.1","source":"security-advisories@github.com"},{"url":"https://github.com/aio-libs/multidict/security/advisories/GHSA-54p9-h82j-f925","source":"security-advisories@github.com"},{"url":"https://github.com/aio-libs/multidict/security/advisories/GHSA-54p9-h82j-f925","source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-104874","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}