SB20260728135 - Anolis OS update for kernel:6.6



SB20260728135 - Anolis OS update for kernel:6.6

Published: July 28, 2026

Security Bulletin ID SB20260728135
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 6
Exploitation vector Local access
Highest impact Data manipulation

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 6 vulnerabilities.


1) Use-after-free (CVE-ID: CVE-2026-43499)

CWE-ID: CWE-416 - Use After Free

CVSSv4: 6.8 [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]


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

The vulnerability exists due to use-after-free in remove_waiter() when rolling back a proxy lock from futex_requeue(). A local user can trigger the affected rtmutex slowlock and proxy-lock rollback path to cause a denial of service.

The issue can leave waiter task state uncleared and operate on the wrong top priority waiter task.


2) Improper control of a resource through its lifetime (CVE-ID: CVE-2026-43503)

CWE-ID: CWE-664 - Improper control of a resource through its lifetime

CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a local user to modify the page cache of a root-owned read-only file.

The vulnerability exists due to improper state management in frag-transfer helpers in the Linux kernel networking stack when moving fragment descriptors between socket buffers. A local user can trigger packet processing through a duplicated skb path to modify the page cache of a root-owned read-only file.

One demonstrated path involves ESP input after a packet is duplicated through an nft 'dup to' rule or another nf_dup_ipv4() / xt_TEE caller.


3) Use-after-free (CVE-ID: CVE-2026-46242)

CWE-ID: CWE-416 - Use After Free

CVSSv4: 6.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a local user to cause memory corruption.

The vulnerability exists due to a use-after-free in ep_remove() in fs/eventpoll.c when removing epoll file references during a race with file release handling. A local user can trigger a race condition to cause memory corruption.

The issue involves the epoll-watches-epoll case and a concurrent __fput() path that can lead to operations on freed structures.


4) Out-of-bounds write (CVE-ID: CVE-2026-46331)

CWE-ID: CWE-787 - Out-of-bounds write

CVSSv4: 6.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a local user to cause memory corruption.

The vulnerability exists due to an out-of-bounds write in tcf_pedit_act() when processing packet edit actions with typed keys and runtime header offsets. A local user can supply crafted pedit parameters that cause writes to a region that has not been properly copy-on-written to cause memory corruption.

The issue can involve negative offsets such as Ethernet header edits at ingress.


5) NULL pointer dereference (CVE-ID: CVE-2026-53166)

CWE-ID: CWE-476 - NULL Pointer Dereference

CVSSv4: 6.8 [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]


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

The vulnerability exists due to a NULL pointer dereference in remove_waiter() in the futex requeue logic when handling FUTEX_CMP_REQUEUE_PI operations that requeue a non-top waiter which already owns the target PI futex. A local user can trigger a self-deadlock condition to cause a denial of service.


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

CWE-ID: CWE-416 - Use After Free

CVSSv4: 6.8 [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]


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.