CVE-2026-76881
Description
A flaw was found in Wireshark. A NULL pointer dereference vulnerability exists within the CMS (Cryptographic Message Syntax) protocol dissector. This issue can be triggered by processing a specially crafted network capture file, leading to an application crash. A remote attacker could exploit this to cause a denial of service (DoS).
Statement
A NULL pointer dereference was found in the CMS protocol dissector in Wireshark versions 4.4.0 through 4.4.18 and 4.6.0 through 4.6.7. Red Hat Enterprise Linux 6, 7, 8, and 9 ship Wireshark versions prior to the affected range and are not vulnerable. Red Hat Enterprise Linux 10 and Red Hat In-Vehicle OS ship an affected version of Wireshark.
Mitigation
Do not open untrusted packet capture files or capture traffic from untrusted networks with Wireshark.
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 Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 4.7 | 5.5 | 4.7 |
| Attack Vector | Local | Local | Local |
| Attack Complexity | High | Low | High |
| Privileges Required | None | None | None |
| User Interaction | Required | Required | Required |
| Scope | Unchanged | Unchanged | Unchanged |
| Confidentiality | None | None | None |
| Integrity Impact | None | None | None |
| Availability Impact | High | High | High |
Vector
Red Hat: CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:H
NVD: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
cve.org: CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Crash, Exit, or Restart
NULL pointer dereferences usually result in the failure of the process unless exception handling (on some platforms) is available and implemented. Even when exception handling is being used, it can still be very difficult to return the software to a safe state of operation.
Integrity,Confidentiality
Technical Impact: Execute Unauthorized Code or Commands; Read Memory; Modify Memory
In rare circumstances, when NULL is equivalent to the 0x0 memory address and privileged code can access it, then writing or reading memory is possible, which may lead to code execution.
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