SB2026071640 - SUSE update for the Linux Kernel (Live Patch 83 for SUSE Linux Enterprise 12 SP5)



SB2026071640 - SUSE update for the Linux Kernel (Live Patch 83 for SUSE Linux Enterprise 12 SP5)

Published: July 16, 2026

Security Bulletin ID SB2026071640
CSH Severity
High
Patch available
YES
Number of vulnerabilities 3
Exploitation vector Remote access
Highest impact Code execution

Breakdown by Severity

High 33% Low 67%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 3 vulnerabilities.


1) Stack-based buffer overflow (CVE-ID: CVE-2026-43037)

CWE-ID: CWE-121 - Stack-based buffer overflow

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


The vulnerability allows a remote attacker to execute arbitrary code.

The vulnerability exists due to a stack-based buffer overflow in ip4ip6_err() and __ip_options_echo() when processing a crafted packet that triggers ICMP error handling on a cloned skb. A remote attacker can send a specially crafted packet to execute arbitrary code.

The issue is caused by reusing skb cb[] data written by the IPv6 receive path as IPv4 metadata, allowing attacker-controlled packet data to influence the copied option length.


2) Use-after-free (CVE-ID: CVE-2026-45970)

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 rlb_arp_recv function in the bonding ALB RX path when processing ARP messages during rapid bond up/down cycles. A local user can trigger concurrent bond up/down operations while ARP traffic is being received to cause a denial of service.

The issue is triggered by a race condition between rlb_arp_recv() and rlb_deinitialize().


3) Improper input validation (CVE-ID: CVE-2026-46243)

CWE-ID: CWE-20 - Improper input validation

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


The vulnerability allows a local user to disclose sensitive information, modify data, or cause a denial of service.

The vulnerability exists due to improper input validation in the cifs.spnego key description handling in fs/smb/client/cifs_spnego.c when processing userspace-created cifs.spnego keys through request_key(2) or add_key(2). A local user can supply a crafted cifs.spnego description to disclose sensitive information, modify data, or cause a denial of service.

The issue arises because authority-bearing fields such as pid, uid, creduid, and upcall_target may be treated by cifs.upcall as kernel-originating inputs.


Remediation

Install update from vendor's website.