CVE-2026-76928

Description

A flaw in Wireshark's X.509IF protocol dissector allows a remote attacker to cause a Denial of Service (DoS). By providing a specially crafted capture file or network stream, an attacker can crash the application, making it unavailable.

Statement

A Moderate Denial of Service vulnerability in Wireshark's X.509IF dissector allows an attacker to crash the application using a crafted capture file or network stream. The impact is limited strictly to Wireshark's availability and does not affect the host system. RHEL 9 and older versions are not affected.

Mitigation

Avoid opening untrusted capture files or monitoring untrusted networks where malformed packets may be broadcast. If X.509IF protocol analysis is not required, disable the dissector. In Wireshark, navigate to Analyze > Enabled Protocols and uncheck X.509IF, or run tshark using the flag -d x509if,0 to bypass this dissector entirely.

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 Score6.5N/A7.5
Attack VectorNetworkN/ANetwork
Attack ComplexityLowN/ALow
Privileges RequiredNoneN/ANone
User InteractionRequiredN/ANone
ScopeUnchangedN/AUnchanged
ConfidentialityNoneN/ANone
Integrity ImpactNoneN/ANone
Availability ImpactHighN/AHigh

Vector

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

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

Understanding the Weakness (CWE)

Confidentiality

Technical Impact: Read Memory

If the expired pointer is used in a read operation, an attacker might be able to control data read in by the application.

Availability

Technical Impact: DoS: Crash, Exit, or Restart

If the expired 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 expired 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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