SB2026051238 - Ubuntu update for linux-azure
Published: May 12, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 18 vulnerabilities.
1) Improper Access Control (CVE-ID: CVE-2026-23268)
CWE-ID: CWE-284 - Improper Access Control
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:H/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 escalate privileges, modify AppArmor security policies, and cause a denial of service.
The vulnerability exists due to improper access control in the AppArmor policy management interface when handling file descriptor operations. A local user can open the apparmorfs interface and pass the file descriptor to a privileged process, tricking it into performing privileged policy management operations on behalf of the user.
The user must have access to a privileged process that can be manipulated to write to the AppArmor interface. Once exploited, the user can load, replace, or remove AppArmor profiles, leading to removal of confinement, denial of service by blocking application execution, bypassing user namespace restrictions, and potentially enabling local privilege escalation via kernel exploits.
2) Out-of-bounds read (CVE-ID: CVE-2026-23269)
CWE-ID: CWE-125 - Out-of-bounds read
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a local user to disclose sensitive information.
The vulnerability exists due to an out-of-bounds read in the AppArmor subsystem's DFA state table validation when processing untrusted policy data. A local user can provide a specially crafted AppArmor policy with an out-of-bounds start state to trigger an out-of-bounds read during policy unpacking.
Exploitation requires the ability to load or modify AppArmor policies, which typically requires privileged access. The out-of-bounds read may expose contents of kernel memory.
3) Memory leak (CVE-ID: CVE-2026-23403)
CWE-ID: CWE-401 - Missing release of memory after effective lifetime
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/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 improper memory management in the AppArmor subsystem when processing multiple profiles during profile unpacking. A local user can provide specially crafted profile data to cause a memory leak, leading to resource exhaustion.
Exploitation requires the ability to load AppArmor profiles, which is restricted to users with appropriate privileges.
4) Uncontrolled Recursion (CVE-ID: CVE-2026-23404)
CWE-ID: CWE-674 - Uncontrolled Recursion
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 attacker to cause a denial of service.
The vulnerability exists due to improper input validation in AppArmor profile removal functionality when handling deeply nested profiles. A local attacker can send a specially crafted request to cause a denial of service.
Exploitation requires the ability to load AppArmor profiles and trigger their removal, which is typically available to unprivileged users on systems where AppArmor is enabled.
5) Resource exhaustion (CVE-ID: CVE-2026-23405)
CWE-ID: CWE-400 - Resource exhaustion
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 improper resource management in the AppArmor policy namespace subsystem when creating nested policy namespaces. A local user can create deeply nested policy namespaces to cause a denial of service.
Exploitation requires the ability to create AppArmor policy namespaces, which is available to unprivileged users in a user namespace.
6) Use-after-free (CVE-ID: CVE-2026-23410)
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 attacker to cause a denial of service.
The vulnerability exists due to a use-after-free in AppArmor rawdata inode handling when opening rawdata files while simultaneously removing the corresponding profile. A local attacker can trigger a race condition to access freed memory and cause a denial of service.
7) Race condition (CVE-ID: CVE-2026-23411)
CWE-ID: CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
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 attacker to cause a denial of service.
The vulnerability exists due to a race condition in the AppArmor i_private data management when accessing filesystem callback functions after reference removal. A local attacker can trigger a use-after-free condition by exploiting the race between freeing data and filesystem access to trigger a denial of service.
The issue arises when the inode persists beyond AppArmor data cleanup and filesystem callbacks are invoked after the reference has been released. This race condition primarily affects data stored in i_private, including rawdata/loaddata interfaces.
8) Use-after-free (CVE-ID: CVE-2026-23209)
CWE-ID: CWE-416 - Use After Free
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 escalate privileges on the system.
The vulnerability exists due to a use-after-free error within the macvlan_common_newlink() function in drivers/net/macvlan.c. A local user can escalate privileges on the system.
9) Use-after-free (CVE-ID: CVE-2026-23074)
CWE-ID: CWE-416 - Use After Free
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 escalate privileges on the system.
The vulnerability exists due to a use-after-free error within the teql_qdisc_init() function in net/sched/sch_teql.c. A local user can escalate privileges on the system.
10) NULL pointer dereference (CVE-ID: CVE-2026-23060)
CWE-ID: CWE-476 - NULL Pointer Dereference
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 NULL pointer dereference within the crypto_authenc_esn_encrypt() and crypto_authenc_esn_decrypt() functions in crypto/authencesn.c. A local user can perform a denial of service (DoS) attack.
11) Memory leak (CVE-ID: CVE-2025-37849)
CWE-ID: CWE-401 - Missing release of memory after effective lifetime
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 memory leak within the kvm_arch_vcpu_create() function in arch/arm64/kvm/arm.c. A local user can perform a denial of service (DoS) attack.
12) Buffer overflow (CVE-ID: CVE-2025-21735)
CWE-ID: CWE-119 - Memory corruption
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 escalate privileges on the system.
The vulnerability exists due to memory corruption within the nci_hci_create_pipe() function in net/nfc/nci/hci.c. A local user can escalate privileges on the system.
13) Input validation error (CVE-ID: CVE-2024-50142)
CWE-ID: CWE-20 - Improper input validation
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 improper input validation within the verify_newsa_info() function in net/xfrm/xfrm_user.c. A local user can perform a denial of service (DoS) attack.
14) Resource management error (CVE-ID: CVE-2024-50008)
CWE-ID: CWE-399 - Resource Management Errors
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 resource management error within the mwifiex_ret_802_11_scan_ext() function in drivers/net/wireless/marvell/mwifiex/scan.c. A local user can perform a denial of service (DoS) attack.
15) Input validation error (CVE-ID: CVE-2024-49938)
CWE-ID: CWE-20 - Improper input validation
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 improper input validation within the ath9k_hif_usb_rx_cb() and ath9k_hif_usb_reg_in_cb() functions in drivers/net/wireless/ath/ath9k/hif_usb.c. A local user can perform a denial of service (DoS) attack.
16) Resource management error (CVE-ID: CVE-2024-46816)
CWE-ID: CWE-399 - Resource Management Errors
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 resource management error within the amdgpu_dm_initialize_drm_device() function in drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c. A local user can perform a denial of service (DoS) attack.
17) Integer overflow (CVE-ID: CVE-2024-46777)
CWE-ID: CWE-190 - Integer overflow
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 execute arbitrary code.
The vulnerability exists due to integer overflow within the udf_fill_partdesc_info() function in fs/udf/super.c. A local user can execute arbitrary code.
18) Memory leak (CVE-ID: CVE-2024-27388)
CWE-ID: CWE-401 - Missing release of memory after effective lifetime
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 memory leak within the gssx_dec_option_array() function in net/sunrpc/auth_gss/gss_rpc_xdr.c. A local user can perform a denial of service (DoS) attack.
Remediation
Install update from vendor's website.