High severity · published Jul 20, 2021
CVE-2021-33909
fs/seq_file.c in the Linux kernel 3.16 through 5.13.x before 5.13.4 does not properly restrict seq buffer allocations, leading to an integer overflow, an Out-of-bounds Write, and…
7.8
CVSS
9.7%
EPSS
No
On KEV
Description
fs/seq_file.c in the Linux kernel 3.16 through 5.13.x before 5.13.4 does not properly restrict seq buffer allocations, leading to an integer overflow, an Out-of-bounds Write, and escalation to root by an unprivileged user, aka CID-8cae8cd89f05.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)9.7% · higher than 95% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KE
Kernel · Linux
3.12.43 before 3.13; 3.16 before 4.4.276; 4.5 before 4.9.276; 4.10 before 4.14.240; 4.15 before 4.19.198; 4.20 before 5.4.134; +3 more · source: NVD
CS
Communications Session Border Controller · Oracle
8.2; 8.3; 8.4; 9.0 · source: NVD
DL
Debian Linux · Debian
9.0; 10.0 · source: NVD
FE
Fedora · Fedoraproject
34 · source: NVD
HM
Hci Management Node · Netapp
All versions, or not specified · source: NVD
SF
Sma1000 Firmware · Sonicwall
through 12.4.2-02044 · source: NVD
SO
Solidfire · Netapp
All versions, or not specified · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-33909
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-33909
Exploit
http://packetstormsecurity.com/files/163621/Sequoia-A-Deep-Root-In-Linuxs-Filesystem-Layer.html
Third Party Advisory
http://packetstormsecurity.com/files/163671/Kernel-Live-Patch-Security-Notice-LSN-0079-1.html
Third Party Advisory
http://packetstormsecurity.com/files/164155/Kernel-Live-Patch-Security-Notice-LSN-0081-1.html
Third Party Advisory
http://packetstormsecurity.com/files/165477/Kernel-Live-Patch-Security-Notice-LSN-0083-1.html
Mailing List
http://www.openwall.com/lists/oss-security/2021/07/22/7
Mailing List
http://www.openwall.com/lists/oss-security/2021/08/25/10
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