Vulnerability · Published Jun 9, 2025 · Assigned by redhat
CVE-2025-47711Nbdkit: nbdkit-server: off-by-one error when processing block status may lead to a denial of service
Medium 6.5
In plain English
A medium-severity security flaw in nbdkit. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 42% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)6.5Medium
Exploit odds (30 days)0.5%top 58.1% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | nbdkit | no fix listed | DEBIAN-CVE-2025-47711 |
| Debian:13 | nbdkit | 1.42.3-1 | DEBIAN-CVE-2025-47711 |
| Debian:14 | nbdkit | 1.42.3-1 | DEBIAN-CVE-2025-47711 |
| Ubuntu:22.04:LTS | nbdkit | no fix listed | UBUNTU-CVE-2025-47711 |
| Ubuntu:24.04:LTS | nbdkit | no fix listed | UBUNTU-CVE-2025-47711 |
| Ubuntu:25.10 | nbdkit | no fix listed | UBUNTU-CVE-2025-47711 |
| Ubuntu:26.04:LTS | nbdkit | no fix listed | UBUNTU-CVE-2025-47711 |
| Ubuntu:26.10 | nbdkit | no fix listed | UBUNTU-CVE-2025-47711 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| nbdkit | 1.11.10 – before 1.38.61.40.0 – before 1.40.61.42.0 – before 1.42.3 | |
| Red Hat | Red Hat Enterprise Linux 10 | see references |
| Red Hat | Red Hat Enterprise Linux 7 | see references |
| Red Hat | Red Hat Enterprise Linux 8 | see references |
| Red Hat | Red Hat Enterprise Linux 8 Advanced Virtualization | see references |
| Red Hat | Red Hat Enterprise Linux 8 Advanced Virtualization | see references |
| Red Hat | Red Hat Enterprise Linux 9 | see references |
Weakness: CWE-193 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
References
- https://access.redhat.com/security/cve/CVE-2025-47711 vdb-entry, x_refsource_REDHAT
- RHBZ#2365687 issue-tracking, x_refsource_REDHAT
- https://lists.libguestfs.org/archives/list/guestfs@lists.libguestfs.org/thread/67E7AASHHADIY7VAD3FFW2I67LTWVWYF/