CVE-2021-33624

Severity CVSS v4.0:

Pending analysis

Type:

Unavailable / Other

Publication date:

23/06/2021

Last modified:

11/11/2025

Description

In kernel/bpf/verifier.c in the Linux kernel before 5.12.13, a branch can be mispredicted (e.g., because of type confusion) and consequently an unprivileged BPF program can read arbitrary memory locations via a side-channel attack, aka CID-9183671af6db.

Impact

Vector 3.x

CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N CVSS v3.1 Severity and Metrics:

Base Score: 4.70 MEDIUM
Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N

Attack Vector (AV): Local
Attack Complexity (AC): High
Privileges Required (PR): Low
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): High
Integrity (I): None
Availability (A): None

Base Score 3.x

4.70

Severity 3.x

MEDIUM

Vector 2.0

AV:L/AC:M/Au:N/C:C/I:N/A:N CVSS v2.0 Severity and Metrics:

Base Score: 4.70 MEDIUM
Vector: AV:L/AC:M/Au:N/C:C/I:N/A:N

Attack Vector (AV): Local
Attack Complexity (AC): Medium
Authentication (Au): None
Confidentiality (C): Complete
Integrity (I): None
Availability (A): None