CVE-2024-36489

Medium

In the Linux kernel, the following vulnerability has been resolved: tls: fix missing memory barrier in tls_init In tls_init(), a write memory barrier is missing, and store-store reordering may cause NULL dereference in tls_{setsockopt,getsockopt}. CPU0 CPU1 ----- ----- // In tls_init() // In tls_ctx_create() ctx = kzalloc() ctx->sk_proto = READ_ONCE(sk->sk_prot) -(1) // In update_sk_prot() WRITE_ONCE(sk->sk_prot, tls_prots) -(2) // In sock_common_setsockopt() READ_ONCE(sk->sk_prot)->setsockopt() // In tls_{setsockopt,getsockopt}() ctx->sk_proto->setsockopt() -(3) In the above scenario, when (1) and (2) are reordered, (3) can observe the NULL value of ctx->sk_proto, causing NULL dereference. To fix it, we rely on rcu_assign_pointer() which implies the release barrier semantic. By moving rcu_assign_pointer() after ctx->sk_proto is initialized, we can ensure that ctx->sk_proto are visible when changing sk->sk_prot.

Package Linux Kernel
Published 2024-06-21
Last modified 2026-05-12
CVSS version 3.1
Patch available
Awaiting data

CVSS 3.1 score

5.5

out of 10
Medium
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
None
Availability
High
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness type

CWE-476

CVE-2024-36489 is a NULL Pointer Dereference vulnerability

What is NULL Pointer Dereference?

The product dereferences a pointer that it expects to be valid but is NULL, typically causing a crash. Learn more on MITRE CWE

References

The following references provide additional information about CVE-2024-36489 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.

Frequently asked questions

  • What is CVE-2024-36489?

    CVE-2024-36489 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 , classified as a NULL Pointer Dereference flaw (CWE-476) . CVE-2024-36489 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

  • What is the CVSS score for CVE-2024-36489?

    CVE-2024-36489 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H .

  • Is there a patch available for CVE-2024-36489?

    No patch is currently available for CVE-2024-36489. Monitor the NIST NVD and your Linux distribution's security advisories for updates.

  • Is CVE-2024-36489 actively exploited?

    No — CVE-2024-36489 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

  • What is NULL Pointer Dereference (CWE-476)?

    The product dereferences a pointer that it expects to be valid but is NULL, typically causing a crash. View CWE-476 on MITRE CWE →