SB20260728159 - SUSE update for the Linux Kernel (Live Patch 46 for SUSE Linux Enterprise 15 SP4)



SB20260728159 - SUSE update for the Linux Kernel (Live Patch 46 for SUSE Linux Enterprise 15 SP4)

Published: July 28, 2026

Security Bulletin ID SB20260728159
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities 5
Exploitation vector Remote access
Highest impact Denial of service

Breakdown by Severity

Medium 40% Low 60%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 5 vulnerabilities.


1) Double free (CVE-ID: CVE-2026-23240)

CWE-ID: CWE-415 - Double Free

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear


The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to a double free error within the tls_sw_cancel_work_tx() function in net/tls/tls_sw.c. A local user can perform a denial of service (DoS) attack.


2) Out-of-bounds read (CVE-ID: CVE-2026-31738)

CWE-ID: CWE-125 - Out-of-bounds read

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green


The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to an out-of-bounds read in vxlan_na_create when parsing neighbor discovery options. A remote attacker can send a specially crafted packet to cause a denial of service.


3) Out-of-bounds read (CVE-ID: CVE-2026-43038)

CWE-ID: CWE-125 - Out-of-bounds read

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green


The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to an out-of-bounds read in ip6_err_gen_icmpv6_unreach() when processing a forged ICMPv4 error containing a CIPSO IP option and an attacker-controlled inner IPv6 packet. A remote attacker can send a specially crafted ICMP error packet to cause a denial of service.

The issue arises because IPv4 control buffer data is reused as IPv6 control buffer data in a cloned skb, which can lead to a forged home address option offset being used during IPv6 TLV parsing.


4) Use-after-free (CVE-ID: CVE-2026-46113)

CWE-ID: CWE-416 - Use After Free

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear


The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to a use-after-free in KVM shadow paging when handling guest page table changes between VM entries. A local user can modify guest page tables to create a stale reverse-mapping entry and trigger a stale rmap walk to cause a denial of service.

This can be triggered during operations such as dirty logging or MMU notifier invalidations.


5) Use-after-free (CVE-ID: CVE-2026-53359)

CWE-ID: CWE-416 - Use After Free

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear


The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to a use-after-free in the KVM x86 shadow paging logic when changing a PDE mapping from outside the guest and deleting a memslot. A local user can trigger stale rmap entries and subsequent dereference of a freed sptep to cause a denial of service.

The issue occurs when a modified PDE points to a non-leaf page, causing a role mismatch between reused shadow pages for large 2MB mappings and new 4KB mappings.


Remediation

Install update from vendor's website.