SB2026040268 - Ubuntu update for linux

Description

This security bulletin contains information about 7 secuirty vulnerabilities.

1) Use-after-free (CVE-ID: CVE-2026-23074)

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.

2) NULL pointer dereference (CVE-ID: CVE-2026-23060)

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.

3) Buffer overflow (CVE-ID: CVE-2025-21735)

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.

4) Integer overflow (CVE-ID: CVE-2024-46777)

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.

5) Use-after-free (CVE-ID: CVE-2021-47254)

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a use-after-free error within the __acquires() and gfs2_scan_glock_lru() functions in fs/gfs2/glock.c. A local user can escalate privileges on the system.

6) Improper error handling (CVE-ID: CVE-2021-47145)

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

The vulnerability exists due to improper error handling within the link_to_fixup_dir() function in fs/btrfs/tree-log.c. A local user can perform a denial of service (DoS) attack.

7) Use-after-free (CVE-ID: CVE-2021-47142)

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a use-after-free error within the amdgpu_ttm_tt_unpopulate() function in drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c. A local user can escalate privileges on the system.

Remediation

Install update from vendor's website.

References

• https://ubuntu.com/security/notices/USN-8143-1