// For flags

CVE-2021-31829

kernel: protection of stack pointer against speculative pointer arithmetic can be bypassed to leak content of kernel memory

Severity Score

5.5
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

kernel/bpf/verifier.c in the Linux kernel through 5.12.1 performs undesirable speculative loads, leading to disclosure of stack content via side-channel attacks, aka CID-801c6058d14a. The specific concern is not protecting the BPF stack area against speculative loads. Also, the BPF stack can contain uninitialized data that might represent sensitive information previously operated on by the kernel.

El archivo kernel/bpf/verifier.c en el kernel de Linux versiones hasta 5.12.1, lleva a cabo cargas especulativas no deseadas, conllevando a una divulgación del contenido de la pila por medio de ataques side-channel, también se conoce como CID-801c6058d14a. La preocupación específica no es proteger el área de la pila de BPF contra cargas especulativas. Además, la pila de BPF puede contener datos no inicializados que pueden representar información confidencial previamente operada por el kernel

A flaw was found in the Linux kernel's eBPF verification code. By default, accessing the eBPF verifier is only accessible to privileged users with CAP_SYS_ADMIN. This flaw allows a local user who can insert eBPF instructions, to use the eBPF verifier to abuse a spectre-like flaw and infer all system memory. The highest threat from this vulnerability is to confidentiality.

*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
Privileges Required
None
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
  • 2021-04-27 CVE Reserved
  • 2021-05-06 CVE Published
  • 2023-03-08 EPSS Updated
  • 2024-08-03 CVE Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-200: Exposure of Sensitive Information to an Unauthorized Actor
  • CWE-863: Incorrect Authorization
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"
 <= 5.12.1
Search vendor "Linux" for product "Linux Kernel" and version " <= 5.12.1"
-
Affected
Fedoraproject
Search vendor "Fedoraproject"
 Fedora
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 32
Search vendor "Fedoraproject" for product "Fedora" and version "32"
-
Affected
Fedoraproject
Search vendor "Fedoraproject"
 Fedora
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 33
Search vendor "Fedoraproject" for product "Fedora" and version "33"
-
Affected
Fedoraproject
Search vendor "Fedoraproject"
 Fedora
Search vendor "Fedoraproject" for product "Fedora"
 34
Search vendor "Fedoraproject" for product "Fedora" and version "34"
-
Affected
Debian
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 Debian Linux
Search vendor "Debian" for product "Debian Linux"
 9.0
Search vendor "Debian" for product "Debian Linux" and version "9.0"
-
Affected