CVE-2026-99165
Description
A flaw was found in the Linux kernel's Stream Control Transmission Protocol (SCTP) implementation. This flaw allows a remote peer or local user to cause a denial of service (DoS) through a kernel crash. When message interleaving is enabled, the kernel drops the socket lock while waiting for association establishment or send-buffer availability, allowing handshake processing to free output stream extensions without proper revalidation. When the sending process resumes and accesses the unvalidated stream, it dereferences a null pointer, causing a system panic.
Statement
This vulnerability is evaluated as having Moderate impact because successful exploitation results in a kernel panic and host denial of service, without granting arbitrary code execution or unauthorized data exposure. Typical Red Hat Enterprise Linux configurations do not automatically load the SCTP kernel module unless an administrator explicitly loads it or an active service binds an SCTP socket. Additionally, triggering the flaw requires local unprivileged socket operations and the specific configuration of SCTP message interleaving combined with stream reconfiguration.
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 | 5.5 | N/A | N/A |
| Attack Vector | Local | N/A | N/A |
| Attack Complexity | Low | N/A | N/A |
| Privileges Required | Low | N/A | N/A |
| User Interaction | None | N/A | N/A |
| Scope | Unchanged | N/A | N/A |
| Confidentiality | None | N/A | N/A |
| Integrity Impact | None | N/A | N/A |
| Availability Impact | High | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/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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