CVE-2021-20286
published 2021-03-15CVE-2021-20286: A flaw was found in libnbd 1.7.3. An assertion failure in nbd_unlocked_opt_go in ilb/opt.c may lead to denial of service.
PriorityP48low2.7CVSS 3.1
AVNACLPRHUINSUCNINAL
EPSS
1.14%
62.9th percentile
A flaw was found in libnbd 1.7.3. An assertion failure in nbd_unlocked_opt_go in ilb/opt.c may lead to denial of service.
Affected
13 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | libnbd | < libnbd 1.6.2-1 (bookworm) | libnbd 1.6.2-1 (bookworm) |
| msrc | azl3_libnbd_1.12.1-3_on_azure_linux_3.0 | — | — |
| msrc | azl3_libnbd_1.18.3-1_on_azure_linux_3.0 | — | — |
| msrc | azure_linux_3.0_arm | — | — |
| msrc | azure_linux_3.0_x64 | — | — |
| msrc | cbl_mariner_2.0_arm | — | — |
| msrc | cbl_mariner_2.0_x64 | — | — |
| redhat | enterprise_linux | — | — |
| redhat | libnbd | < 1.7.3 | 1.7.3 |
| redhat | libnbd | — | — |
| redhat | libnbd | >= 0 < 1.6.2-1 | 1.6.2-1 |
| redhat | libnbd | >= 0 < 1.6.2-1 | 1.6.2-1 |
| redhat | libnbd | >= 0 < 1.6.2-1 | 1.6.2-1 |
CVSS provenance
nvdv3.12.7LOWCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:L
nvdv2.04.0MEDIUMAV:N/AC:L/Au:S/C:N/I:N/A:P
osv2.7LOW
vendor_debian2.7LOW
vendor_msrc2.7LOW
vendor_redhat2.7LOW
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Microsoft
A flaw was found in libnbd 1.7.3. An assertion failure in nbd_unlocked_opt_go in ilb/opt.c may lead to denial of service.
vendor_msrc·2021-03-09·CVSS 2.7
CVE-2021-20286 [LOW] CWE-617 A flaw was found in libnbd 1.7.3. An assertion failure in nbd_unlocked_opt_go in ilb/opt.c may lead to denial of service.
A flaw was found in libnbd 1.7.3. An assertion failure in nbd_unlocked_opt_go in ilb/opt.c may lead to denial of service.
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 Requir
Red Hat
libnbd: Assertion failure in nbd_unlocked_opt_go in lib/opt.c
vendor_redhat·2021-03-01·CVSS 2.7
CVE-2021-20286 [LOW] CWE-617 libnbd: Assertion failure in nbd_unlocked_opt_go in lib/opt.c
libnbd: Assertion failure in nbd_unlocked_opt_go in lib/opt.c
A flaw was found in libnbd 1.7.3. An assertion failure in nbd_unlocked_opt_go in ilb/opt.c may lead to denial of service.
A flaw was found in libnbd. A malicious server may be able to kill a client application using libnbd due to an assertion failure in nbd_unlocked_opt_go() leading to denial of service. The highest threat from this vulnerability is to system availability.
Statement: Red Hat Enterprise Linux 8 is not affected by this issue. The affected API was introduced in upstream `libnbd` version 1.4 which is only shipped in RHEL Advanced Virtualization 8.3.0 onward.
Package: virt:rhel/libnbd (Red Hat Enterprise Linux 8) - Not affected
Package: virt:8.2/libnbd (Red Hat Enterprise Linux 8 Advanced Virtualization) - Not a
Debian
CVE-2021-20286: libnbd - A flaw was found in libnbd 1.7.3. An assertion failure in nbd_unlocked_opt_go in...
vendor_debian·2021·CVSS 2.7
CVE-2021-20286 [LOW] CVE-2021-20286: libnbd - A flaw was found in libnbd 1.7.3. An assertion failure in nbd_unlocked_opt_go in...
A flaw was found in libnbd 1.7.3. An assertion failure in nbd_unlocked_opt_go in ilb/opt.c may lead to denial of service.
Scope: local
bookworm: resolved (fixed in 1.6.2-1)
bullseye: open
forky: resolved (fixed in 1.6.2-1)
sid: resolved (fixed in 1.6.2-1)
trixie: resolved (fixed in 1.6.2-1)
GHSA
GHSA-r4rf-vx7w-8692: A flaw was found in libnbd 1
ghsa_unreviewed·2022-05-24
CVE-2021-20286 [MEDIUM] CWE-617 GHSA-r4rf-vx7w-8692: A flaw was found in libnbd 1
A flaw was found in libnbd 1.7.3. An assertion failure in nbd_unlocked_opt_go in ilb/opt.c may lead to denial of service.
OSV
CVE-2021-20286: A flaw was found in libnbd 1
osv·2021-03-15·CVSS 2.7
CVE-2021-20286 [LOW] CVE-2021-20286: A flaw was found in libnbd 1
A flaw was found in libnbd 1.7.3. An assertion failure in nbd_unlocked_opt_go in ilb/opt.c may lead to denial of service.
No detection rules found.
No public exploits indexed.
2021-03-15
Published