High severity · published Feb 18, 2022
CVE-2021-4090
An out-of-bounds (OOB) memory write flaw was found in the NFSD in the Linux kernel
7.1
CVSS
0.3%
EPSS
No
On KEV
Description
An out-of-bounds (OOB) memory write flaw was found in the NFSD in the Linux kernel. Missing sanity may lead to a write beyond bmval[bmlen-1] in nfsd4_decode_bitmap4 in fs/nfsd/nfs4xdr.c. In this flaw, a local attacker with user privilege may gain access to out-of-bounds memory, leading to a system integrity and confidentiality threat.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 27% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KE
Kernel · Linux
5.11 before 5.15.5 · source: vendor, NVD
HF
H300e Firmware · Netapp
All versions, or not specified · source: NVD
HF
H300s Firmware · Netapp
All versions, or not specified · source: NVD
HF
H410c Firmware · Netapp
All versions, or not specified · source: NVD
HF
H410s Firmware · Netapp
All versions, or not specified · source: NVD
HF
H500e Firmware · Netapp
All versions, or not specified · source: NVD
HF
H500s Firmware · Netapp
All versions, or not specified · source: NVD
HF
H700e Firmware · Netapp
All versions, or not specified · source: NVD
HF
H700s Firmware · Netapp
All versions, or not specified · source: NVD
SS
SIMATIC S7-1500 TM MFP - GNU/Linux subsystem · Siemens
before V1.1.1 · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-4090
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-4090
Issue Tracking
https://bugzilla.redhat.com/show_bug.cgi?id=2025101
git.kernel.org
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c0019b7db1d7ac62c711cda6b357a659d46428fe
lore.kernel.org
https://lore.kernel.org/linux-nfs/163692036074.16710.5678362976688977923.stgit%40klimt.1015granger.net/
Third Party Advisory
https://security.netapp.com/advisory/ntap-20220318-0010/
cert-portal.siemens.com
https://cert-portal.siemens.com/productcert/html/ssa-265688.html
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