Description
A flaw exists in the nbdkit "blocksize" filter that can be triggered by a specific type of client request. When a client requests block status information for a very large data range, exceeding a certain limit, it causes an internal error in the nbdkit, leading to a denial of service.
Affected products
nbdkit_project: nbdkit; redhat: enterprise linux; redhat: enterprise linux advanced virtualization
References3
- access.redhat.com/security/cve/CVE-2025-47712 Third Party Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2365724 Issue TrackingThird Party Advisory
- lists.libguestfs.org/archives/list/[email protected]… Third Party Advisory
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 1% percentile: 45 · as of 7 November 2026
- CWE
- CWE-190
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