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Critical severity · published May 25, 2021
CVE-2021-33574
The mq_notify function in the GNU C Library (aka glibc) versions 2.32 and 2.33 has a use-after-free
9.8
CVSS
3.5%
EPSS
No
On KEV
Description
The mq_notify function in the GNU C Library (aka glibc) versions 2.32 and 2.33 has a use-after-free. It may use the notification thread attributes object (passed through its struct sigevent parameter) after it has been freed by the caller, leading to a denial of service (application crash) or possibly unspecified other impact.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)3.5% · higher than 89% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CB
Cloud Backup · Netapp
All versions, or not specified · source: NVD
DL
Debian Linux · Debian
10.0 · source: NVD
ES
E-series Santricity OS Controller · Netapp
11.0 through 11.70.1 · source: NVD
FE
Fedora · Fedoraproject
33; 34 · source: NVD
GL
Glibc · Gnu
2.32; 2.33 · source: NVD
HF
H300e Firmware · Netapp
All versions, or not specified · source: NVD
HF
H300s 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
Affected product
DL
Debian Linux
Debian
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-33574
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-33574
Mailing List
https://lists.debian.org/debian-lts-announce/2022/10/msg00021.html
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/KJYYIMDDYOHTP2PORLABTOHYQYYREZDD/
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RBUUWUGXVILQXVWEOU7N42ICHPJNAEUP/
Third Party Advisory
https://security.gentoo.org/glsa/202107-07
Third Party Advisory
https://security.netapp.com/advisory/ntap-20210629-0005/
Exploit
https://sourceware.org/bugzilla/show_bug.cgi?id=27896
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