CVE-2024-42072

Description

From CVE.org

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix may_goto with negative offset. Zac's syzbot crafted a bpf prog that exposed two bugs in may_goto. The 1st bug is the way may_goto is patched. When offset is negative it should be patched differently. The 2nd bug is in the verifier: when current state may_goto_depth is equal to visited state may_goto_depth it means there is an actual infinite loop. It's not correct to prune exploration of the program at this point. Note, that this check doesn't limit the program to only one may_goto insn, since 2nd and any further may_goto will increment may_goto_depth only in the queued state pushed for future exploration. The current state will have may_goto_depth == 0 regardless of number of may_goto insns and the verifier has to explore the program until bpf_exit.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score5.27.87.8
Attack VectorLocalLocalLocal
Attack ComplexityHighLowLow
Privileges RequiredHighLowLow
User InteractionNoneNoneNone
ScopeUnchangedUnchangedUnchanged
ConfidentialityLowHighHigh
Integrity ImpactLowHighHigh
Availability ImpactHighHighHigh

Vector

Red Hat: CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:L/A:H

NVD: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

cve.org: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Red Hat CVSS v3 Score Explanation

Because this attack requires crafted BPF programs and because the generated program which uncovered this weakness does not constitute a complete proof-of-concept, Red Hat assesses the Attack Complexity and Privileges Required of this vulnerability to be High, and the impact on Confidentiality and Integrity to be Low.

Understanding the Weakness (CWE)

Confidentiality

Technical Impact: Read Memory

If the untrusted pointer is used in a read operation, an attacker might be able to read sensitive portions of memory.

Availability

Technical Impact: DoS: Crash, Exit, or Restart

If the untrusted pointer references a memory location that is not accessible to the product, or points to a location that is "malformed" or larger than expected by a read or write operation, the application may terminate unexpectedly.

Integrity,Confidentiality,Availability

Technical Impact: Execute Unauthorized Code or Commands; Modify Memory

If the untrusted pointer is used in a function call, or points to unexpected data in a write operation, then code execution may be possible.

Frequently Asked Questions

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