CVE-2025-47711
nbdkit: nbdkit-server: off-by-one error when processing block status may lead to a Denial of Service
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · April 23, 2025
Updated · June 30, 2026
Description
There's a flaw in the nbdkit server when handling responses from its plugins regarding the status of data blocks. If a client makes a specific request for a very large data range, and a plugin responds with an even larger single block, the nbdkit server can encounter a critical internal error, leading to a denial-of-service.
Statement
This vulnerability was rated as a Moderate severity by the Red Hat Product Security team. Based on the fact that while this vulnerability can be exploited remotely (AV:N) with relative ease (AC:L), it does require the attacker to have valid credentials to the target (PR:L). The primary impact is a temporary denial-of-service (A:L), meaning the server becomes unavailable, potentially disrupting dependent services. However, this exploitation does not lead to any compromise of data confidentiality (C:N) or integrity (I:N).
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.1 · 6.5CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CWE-193 · Off-by-one Error