// For flags

CVE-2020-36557

kernel: race condition between the VT_DISALLOCATE ioctl and closing/opening of ttys, causing a use-after-free in con_shutdown().

Severity Score

5.1
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

A race condition in the Linux kernel before 5.6.2 between the VT_DISALLOCATE ioctl and closing/opening of ttys could lead to a use-after-free.

Una condición de carrera en el kernel de Linux versiones anteriores a 5.6.2 entre el ioctl VT_DISALLOCATE y el cierre/apertura de ttys podría conllevar a un uso de memoria previamente liberada

A use-after-free flaw was found in the Linux kernel’s Virtual Terminal subsystem in how a user calls the VT_DISALLOCATE ioctl during the closing/opening of ttys. This flaw allows a local user to crash the system.

*Credits: N/A
CVSS Scores
Attack Vector
Local
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2022-07-21 CVE Reserved
  • 2022-07-21 CVE Published
  • 2024-02-11 EPSS Updated
  • 2024-08-04 CVE Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
  • CWE-416: Use After Free
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Linux
Search vendor "Linux"
 Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
 < 5.6.2
Search vendor "Linux" for product "Linux Kernel" and version " < 5.6.2"
-
Affected