Medium severity · published Mar 20, 2021
CVE-2021-28951
An issue was discovered in fs/io_uring.c in the Linux kernel through 5.11.8
5.5
CVSS
0.3%
EPSS
No
On KEV
Description
An issue was discovered in fs/io_uring.c in the Linux kernel through 5.11.8. It allows attackers to cause a denial of service (deadlock) because exit may be waiting to park a SQPOLL thread, but concurrently that SQPOLL thread is waiting for a signal to start, aka CID-3ebba796fa25.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 20% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KE
Kernel · Linux
through 5.11.8 · source: NVD
AF
A250 Firmware · Netapp
All versions, or not specified · source: NVD
A5
Aff 500f Firmware · Netapp
All versions, or not specified · source: NVD
CB
Cloud Backup · Netapp
All versions, or not specified · source: NVD
F5
Fas 500f Firmware · Netapp
All versions, or not specified · source: NVD
FE
Fedora · Fedoraproject
32; 33; 34 · source: NVD
SB
Solidfire Baseboard Management Controller Firmware · Netapp
All versions, or not specified · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-28951
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-28951
Patch
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=3ebba796fa251d042be42b929a2d916ee5c34a49
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4VCKIOXCOZGXBEZMO5LGGV5MWCHO6FT3/
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PTRNPQTZ4GVS46SZ4OBXY5YDOGVPSTGQ/
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/T2S3I4SLRNRUQDOFYUS6IUAZMQNMPNLG/
Third Party Advisory
https://security.netapp.com/advisory/ntap-20210430-0003/
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