CVE-2025-40281
Description
A shift-out-of-bounds flaw was found in the SCTP implementation in the Linux kernel. When rto_alpha or rto_beta sysctl values are set excessively large, sctp_transport_update_rto() can perform a bit shift with an exponent exceeding the type's bit width, causing undefined behavior per UBSAN.
Statement
Triggering requires either malicious sysctl settings (privileged) or unusual SCTP configurations. Default values are safe. UBSAN catches this as undefined behavior, but practical exploitation for code execution is unlikely.
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 | 4.4 | N/A | N/A |
| Attack Vector | Local | N/A | N/A |
| Attack Complexity | Low | N/A | N/A |
| Privileges Required | High | 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:H/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Integrity
Technical Impact: DoS: Crash, Exit, or Restart
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