CVE-2023-5215

Name: CVE-2023-5215
Creator: NVD / NIST
Published: 2023-09-28T14:15:26.117+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.5/10EPSS 0.75%

Last modified Jun 17, 2026

CVE-2023-5215 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. A flaw was found in libnbd. A server can reply with a block size larger than 2^63 (the NBD spec states the size is a 64-bit unsigned value). EPSS estimates a 0.75% chance of exploitation in the next 30 days.

Description

A flaw was found in libnbd. A server can reply with a block size larger than 2^63 (the NBD spec states the size is a 64-bit unsigned value). This issue could lead to an application crash or other unintended behavior for NBD clients that doesn't treat the return value of the nbd_get_size() function correctly.

Metrics

CVSS 3.1

6.5/10

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

0.75%

50.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Redhat	Libnbd	< 1.18.0
Redhat	Enterprise Linux	8.0
Redhat	Enterprise Linux	9.0

References

https://access.redhat.com/errata/RHSA-2024:2204
https://access.redhat.com/security/cve/CVE-2023-5215Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2241041Issue Tracking, Vendor Advisory
https://listman.redhat.com/archives/libguestfs/2023-September/032635.htmlExploit, Patch
https://access.redhat.com/errata/RHSA-2024:2204
https://access.redhat.com/security/cve/CVE-2023-5215Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2241041Issue Tracking, Vendor Advisory
https://listman.redhat.com/archives/libguestfs/2023-September/032635.htmlExploit, Patch

Timeline

Published: Sep 28, 2023
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2023-5215?

How severe is CVE-2023-5215?

CVE-2023-5215 has a CVSS score of 6.5/10 (MEDIUM severity). The EPSS model estimates a 0.75% probability of exploitation in the next 30 days.

How do I fix CVE-2023-5215?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2023-5215?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST