Low severity · published Aug 18, 2021
CVE-2021-21781
An information disclosure vulnerability exists in the ARM SIGPAGE functionality of Linux Kernel v5.4.66 and v5.4.54
3.3
CVSS
0.5%
EPSS
No
On KEV
Description
An information disclosure vulnerability exists in the ARM SIGPAGE functionality of Linux Kernel v5.4.66 and v5.4.54. The latest version (5.11-rc4) seems to still be vulnerable. A userland application can read the contents of the sigpage, which can leak kernel memory contents. An attacker can read a process’s memory at a specific offset to trigger this vulnerability. This was fixed in kernel releases: 4.14.222 4.19.177 5.4.99 5.10.17 5.11
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 42% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KE
Kernel · Linux
5.4.54; 5.4.66 · source: NVD
CC
Communications Cloud Native Core Binding Support Function · Oracle
22.1.3 · source: NVD
CC
Communications Cloud Native Core Network Exposure Function · Oracle
22.1.1 · source: NVD
CC
Communications Cloud Native Core Policy · Oracle
22.2.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-21781
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-21781
Exploit
https://talosintelligence.com/vulnerability_reports/TALOS-2021-1243
Patch
https://www.oracle.com/security-alerts/cpujul2022.html
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