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Advisory details: pypa / nova/PYSEC-2026-2686
Advisory ID pypa/nova/PYSEC-2026-2686
Aliases CVE-2026-46448
GHSA-mfg3-p6m3-gjgr
PYSEC-2026-2686
Summary OpenStack Nova: Nova scheduler hint injection bypasses Placement resource claims and scheduling constraints ## Affects - Nova: >=18.0.0 <31.3.1, >=32.0.0 <32.2.1, >=33.0.0 <33.0.2 ## Description Erichen from the Institute of Computing Technology, Chinese Academy of Sciences reported that Nova's server create API does not strip internal scheduler hints. An authenticated user can bypass Placement resource claims and scheduling constraint enforcement, including availability zone, host aggregate, and image trait restrictions. The resulting instance has no Placement allocation, which can lead to compute node resource exhaustion and cross-tenant data persistence on NVMe devices after instance deletion. Deployments running Nova 18.0.0 or later are affected. ## Patches - https://review.opendev.org/993604 (2025.1/epoxy) - https://review.opendev.org/993603 (2025.2/flamingo) - https://review.opendev.org/993602 (2026.1/gazpacho) - https://review.opendev.org/993601 (2026.2/hibiscus) ## Credits - Erichen from Institute of Computing Technology, Chinese Academy of Sciences (CVE-2026-46448)
Status Published
Exploitability 0.5
Weighted Severity 4.9
Risk 2.5
Affected and Fixed Packages Package Details
Introduced and Fixed Package Commit Patches Package Commit Patches Details
Weaknesses (0)
There are no known CWE.

No exploits are available.

No EPSS data available for this advisory.

Patch URL
There are no known patches.
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:L Found at https://github.com/pypa/advisory-database/blob/main/vulns/nova/PYSEC-2026-2686.yaml
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none

Vector: SSVCv2/E:P/A:N/T:P/P:M/B:A/M:M/D:T/2026-06-17T12:17:00Z/

Decision: Track

Source URL: https://github.com/cisagov/vulnrichment/blob/develop/2026/46xxx/CVE-2026-46448.json

Source Advisory: vulnrichment/CVE-2026-46448

View SSVC decision tree
[{'Exploitation': 'poc'},
 {'Automatable': 'no'},
 {'Technical Impact': 'partial'},
 {'Mission Prevalence': 'minimal'},
 {'Public Well-being Impact': 'material'},
 {'Mission & Well-being': 'medium'}]