CVE-2026-53218

Description

A flaw was found in the Linux kernel's netfilter component. This vulnerability occurs in the nft_exthdr module when handling user-controlled data lengths with a specific flag, NFT_EXTHDR_F_PRESENT, enabled. An attacker could exploit this by providing a crafted input, leading to the exposure of uninitialized stack memory. This information disclosure could potentially reveal sensitive system data.

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 Score75.5N/A
Attack VectorLocalLocalN/A
Attack ComplexityHighLowN/A
Privileges RequiredLowLowN/A
User InteractionNoneNoneN/A
ScopeUnchangedUnchangedN/A
ConfidentialityHighNoneN/A
Integrity ImpactHighNoneN/A
Availability ImpactHighHighN/A

Vector

Red Hat: CVSS:3.1/AV:L/AC:H/PR:L/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:N/I:N/A:H

Understanding the Weakness (CWE)

Confidentiality

Technical Impact: Read Memory

If the uninitialized 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 uninitialized pointer references a memory location that is not accessible to the product, or points to a location that is "malformed" (such as NULL) or larger than expected by a read or write operation, then a crash may occur.

Integrity,Confidentiality,Availability

Technical Impact: Execute Unauthorized Code or Commands

If the uninitialized 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

Want to get errata notifications? Sign up here.