CVE-2026-74587

A flaw was found in the Linux kernel's Stream Control Transmission Protocol (SCTP) implementation. During peer restart handling, the system improperly releases a cached ASCONF chunk without clearing its pointer, leading to a use-after-free vulnerability. A remote attacker could exploit this by sending a delayed authenticated ASCONF-ACK, causing the system to access freed memory. This could result in a system crash, leading to a denial of service.

This vulnerability is rated as Moderate severity rather than Important because exploitation requires an established SCTP session and precise race timing during peer restart operations. On typical Red Hat Enterprise Linux installations, the SCTP module is not loaded by default and is only present when explicitly needed by specialized network services. While memory corruption could lead to a kernel crash and denial of service, the requirement for an active association and authenticated control chunks substantially bounds real-world exposure.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.