CVE-2022-49478

Description

From CVE.org

In the Linux kernel, the following vulnerability has been resolved: media: pvrusb2: fix array-index-out-of-bounds in pvr2_i2c_core_init Syzbot reported that -1 is used as array index. The problem was in missing validation check. hdw->unit_number is initialized with -1 and then if init table walk fails this value remains unchanged. Since code blindly uses this member for array indexing adding sanity check is the easiest fix for that. hdw->workpoll initialization moved upper to prevent warning in __flush_work.

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 Score6.77.87.8
Attack VectorLocalLocalLocal
Attack ComplexityLowLowLow
Privileges RequiredHighLowLow
User InteractionNoneNoneNone
ScopeUnchangedUnchangedUnchanged
ConfidentialityHighHighHigh
Integrity ImpactHighHighHigh
Availability ImpactHighHighHigh

Vector

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

The successful exploitation of this vulnerability requires close to root-level privileges, which is why the CVSS has been marked as such.

Understanding the Weakness (CWE)

Integrity,Availability

Technical Impact: DoS: Crash, Exit, or Restart

Use of an index that is outside the bounds of an array will very likely result in the corruption of relevant memory and perhaps instructions, leading to a crash, if the values are outside of the valid memory area.

Integrity

Technical Impact: Modify Memory

If the memory corrupted is data, rather than instructions, the system will continue to function with improper values.

Confidentiality,Integrity

Technical Impact: Modify Memory; Read Memory

Use of an index that is outside the bounds of an array can also trigger out-of-bounds read or write operations, or operations on the wrong objects; i.e., "buffer overflows" are not always the result. This may result in the exposure or modification of sensitive data.

Integrity,Confidentiality,Availability

Technical Impact: Execute Unauthorized Code or Commands

If the memory accessible by the attacker can be effectively controlled, it may be possible to execute arbitrary code, as with a standard buffer overflow and possibly without the use of large inputs if a precise index can be controlled.

Integrity,Availability,Confidentiality

Technical Impact: DoS: Crash, Exit, or Restart; Execute Unauthorized Code or Commands; Read Memory; Modify Memory

A single fault could allow either an overflow (CWE-788) or underflow (CWE-786) of the array index. What happens next will depend on the type of operation being performed out of bounds, but can expose sensitive information, cause a system crash, or possibly lead to arbitrary code execution.

Frequently Asked Questions

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