// For flags

CVE-2021-45402

Ubuntu Security Notice USN-5337-1

Severity Score

5.5
*CVSS v3.1

Exploit Likelihood

< 1%
*EPSS

Affected Versions

6
*CPE

Public Exploits

2
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

The check_alu_op() function in kernel/bpf/verifier.c in the Linux kernel through v5.16-rc5 did not properly update bounds while handling the mov32 instruction, which allows local users to obtain potentially sensitive address information, aka a "pointer leak."

La función check_alu_op() en el archivo kernel/bpf/verifier.c en el kernel de Linux versiones hasta v5.16-rc5, no actualizaba correctamente los límites mientras manejaba la instrucción mov32, que permite a usuarios locales obtener información de direcciones potencialmente confidencial, también se conoce como "pointer leak."

It was discovered that the BPF verifier in the Linux kernel did not properly restrict pointer types in certain situations. A local attacker could use this to cause a denial of service or possibly execute arbitrary code. Yiqi Sun and Kevin Wang discovered that the cgroups implementation in the Linux kernel did not properly restrict access to the cgroups v1 release_agent feature. A local attacker could use this to gain administrative privileges.

*Credits: N/A
CVSS Scores
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None
Attack Vector
Local
Attack Complexity
Low
Authentication
None
Confidentiality
Partial
Integrity
None
Availability
None
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2021-12-20 CVE Reserved
  • 2022-02-11 CVE Published
  • 2024-08-04 CVE Updated
  • 2024-08-04 First Exploit
  • 2025-03-30 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
CWE
  • CWE-668: Exposure of Resource to Wrong Sphere
CAPEC
Affected Vendors, Products, and Versions (6)