CVE-2023-5215
published 2023-09-28CVE-2023-5215: 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…
PriorityP422medium6.5CVSS 3.1
AVAACLPRNUINSUCNINAH
EPSS
0.75%
50.6th percentile
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.
Affected
12 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | libnbd | < libnbd 1.16.5-1 (forky) | libnbd 1.16.5-1 (forky) |
| msrc | azl3_libnbd_1.12.1-3_on_azure_linux_3.0 | — | — |
| msrc | azure_linux_3.0_arm | — | — |
| msrc | azure_linux_3.0_x64 | — | — |
| msrc | cbl2_libnbd_1.12.1-3_on_cbl_mariner_2.0 | — | — |
| msrc | cbl_mariner_2.0_arm | — | — |
| msrc | cbl_mariner_2.0_x64 | — | — |
| redhat | enterprise_linux | — | — |
| redhat | enterprise_linux | — | — |
| redhat | libnbd | < 1.18.0 | 1.18.0 |
| redhat | libnbd | >= 0 < 1.16.5-1 | 1.16.5-1 |
| redhat | libnbd | >= 0 < 1.16.5-1 | 1.16.5-1 |
CVSS provenance
nvdv3.16.5MEDIUMCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
osv6.5MEDIUM
vendor_msrc6.5MEDIUM
vendor_debian5.3MEDIUM
vendor_redhat5.3MEDIUM
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OSV
CVE-2023-5215: A flaw was found in libnbd
osv·2023-09-28·CVSS 6.5
CVE-2023-5215 [MEDIUM] CVE-2023-5215: A flaw was found in libnbd
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.
GHSA
GHSA-fj2q-5f6j-5xf4: A flaw was found in libnbd
ghsa_unreviewed·2023-09-28
CVE-2023-5215 [MEDIUM] CWE-241 GHSA-fj2q-5f6j-5xf4: A flaw was found in libnbd
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.
Red Hat
libnbd: Crash or misbehaviour when NBD server returns an unexpected block size
vendor_redhat·2023-09-21·CVSS 5.3
CVE-2023-5215 [MEDIUM] CWE-241 libnbd: Crash or misbehaviour when NBD server returns an unexpected block size
libnbd: Crash or misbehaviour when NBD server returns an unexpected block size
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.
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.
Package: virt:rhel/libnbd (Red Hat Enterprise Linux 8) - Fix deferred
Package: virt:av/libnbd (Re
Microsoft
Libnbd: crash or misbehaviour when nbd server returns an unexpected block size
vendor_msrc·2023-09-12·CVSS 6.5
CVE-2023-5215 [MEDIUM] CWE-252 Libnbd: crash or misbehaviour when nbd server returns an unexpected block size
Libnbd: crash or misbehaviour when nbd server returns an unexpected block size
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.
Mariner: Mariner
redhat: redhat
Customer Action Required: Yes
Remediation: CBL-Mariner Releases
Debian
CVE-2023-5215: libnbd - A flaw was found in libnbd. A server can reply with a block size larger than 2^6...
vendor_debian·2023·CVSS 5.3
CVE-2023-5215 [MEDIUM] CVE-2023-5215: libnbd - A flaw was found in libnbd. A server can reply with a block size larger than 2^6...
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.
Scope: local
bookworm: open
bullseye: open
forky: resolved (fixed in 1.16.5-1)
sid: resolved (fixed in 1.16.5-1)
trixie: resolved (fixed in 1.16.5-1)
No detection rules found.
No public exploits indexed.
https://access.redhat.com/errata/RHSA-2024:2204https://access.redhat.com/security/cve/CVE-2023-5215https://bugzilla.redhat.com/show_bug.cgi?id=2241041https://listman.redhat.com/archives/libguestfs/2023-September/032635.htmlhttps://access.redhat.com/errata/RHSA-2024:2204https://access.redhat.com/security/cve/CVE-2023-5215https://bugzilla.redhat.com/show_bug.cgi?id=2241041https://listman.redhat.com/archives/libguestfs/2023-September/032635.html
2023-09-28
Published