Attacker Value
Unknown
(0 users assessed)
Exploitability
Unknown
(0 users assessed)
User Interaction
None
Privileges Required
Low
Attack Vector
Local
0

CVE-2024-45020

Disclosure Date: September 11, 2024
Add MITRE ATT&CK tactics and techniques that apply to this CVE.

Description

In the Linux kernel, the following vulnerability has been resolved:

bpf: Fix a kernel verifier crash in stacksafe()

Daniel Hodges reported a kernel verifier crash when playing with sched-ext.
Further investigation shows that the crash is due to invalid memory access
in stacksafe(). More specifically, it is the following code:

if (exact != NOT_EXACT &&
    old->stack[spi].slot_type[i % BPF_REG_SIZE] !=
    cur->stack[spi].slot_type[i % BPF_REG_SIZE])
        return false;

The ‘i’ iterates old->allocated_stack.
If cur->allocated_stack < old->allocated_stack the out-of-bound
access will happen.

To fix the issue add ‘i >= cur->allocated_stack’ check such that if
the condition is true, stacksafe() should fail. Otherwise,
cur->stack[spi].slot_type[i % BPF_REG_SIZE] memory access is legal.

Add Assessment

No one has assessed this topic. Be the first to add your voice to the community.

CVSS V3 Severity and Metrics
Base Score:
5.5 Medium
Impact Score:
3.6
Exploitability Score:
1.8
Vector:
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector (AV):
Local
Attack Complexity (AC):
Low
Privileges Required (PR):
Low
User Interaction (UI):
None
Scope (S):
Unchanged
Confidentiality (C):
None
Integrity (I):
None
Availability (A):
High

General Information

Additional Info

Technical Analysis