# CVE-2026-53041: ocfs2: fix listxattr handling when the buffer is full

> A local attacker can trigger a kernel crash in the OCFS2 filesystem by exploiting a buffer overflow in listxattr handling when inline and block xattrs are present.

- **Severity:** High 7.1 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 24 Jun 2026
- **Updated:** 5 Aug 2026
- **Also known as:** BELL-CVE-2026-53041, DEBIAN-CVE-2026-53041, GHSA-gmx4-g5vq-2x9x, ROOT-OS-DEBIAN-11-CVE-2026-53041, ROOT-OS-DEBIAN-12-CVE-2026-53041, ROOT-OS-UBUNTU-2204-CVE-2026-53041, ROOT-OS-UBUNTU-2404-CVE-2026-53041, UBUNTU-CVE-2026-53041

## What is CVE-2026-53041?

CVE-2026-53041 is a high-severity memory corruption vulnerability in Linux kernel, published on 24 Jun 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

ocfs2: fix listxattr handling when the buffer is full

[BUG]
If an OCFS2 inode has both inline and block-based xattrs, listxattr()
can return a size larger than the caller's buffer when the inline names
consume that buffer exactly.

kernel BUG at mm/usercopy.c:102!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
RIP: 0010:usercopy_abort+0xb7/0xd0 mm/usercopy.c:102
Call Trace:
 __check_heap_object+0xe3/0x120 mm/slub.c:8243
 check_heap_object mm/usercopy.c:196 [inline]
 __check_object_size mm/usercopy.c:250 [inline]
 __check_object_size+0x5c5/0x780 mm/usercopy.c:215
 check_object_size include/linux/ucopysize.h:22 [inline]
 check_copy_size include/linux/ucopysize.h:59 [inline]
 copy_to_user include/linux/uaccess.h:219 [inline]
 listxattr+0xb0/0x170 fs/xattr.c:926
 filename_listxattr fs/xattr.c:958 [inline]
 path_listxattrat+0x137/0x320 fs/xattr.c:988
 __do_sys_listxattr fs/xattr.c:1001 [inline]
 __se_sys_listxattr fs/xattr.c:998 [inline]
 __x64_sys_listxattr+0x7f/0xd0 fs/xattr.c:998
 ...

[CAUSE]
Commit 936b8834366e ("ocfs2: Refactor xattr list and remove
ocfs2_xattr_handler().") replaced the old per-handler list accounting
with ocfs2_xattr_list_entry(), but it kept using size == 0 to detect
probe mode.

That assumption stops being true once ocfs2_listxattr() finishes the
inline-xattr pass. If the inline names fill the caller buffer exactly,
the block-xattr pass runs with a non-NULL buffer and a remaining size of
zero. ocfs2_xattr_list_entry() then skips the bounds check, keeps
counting block names, and returns a positive size larger than the
supplied buffer.

[FIX]
Detect probe mode by testing whether the destination buffer pointer is
NULL instead of whether the remaining size is zero.

That restores the pre-refactor behavior and matches the OCFS2 getxattr
helpers. Once the remaining buffer reaches zero while more names are
left, the block-xattr pass now returns -ERANGE instead of reporting a
size larger than the allocated list buffer.

Weakness: CWE-787 (Out-of-bounds Write)

## Which versions are affected by CVE-2026-53041?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-53041?

Apply the vendor's patch.

## Is CVE-2026-53041 being exploited?

There is no known exploitation of CVE-2026-53041 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-53041 and fix it if it is affected.

What it is: CVE-2026-53041 is a high-severity memory corruption vulnerability in Linux kernel, published on 24 Jun 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-53041 in the wild and no public exploit code.

Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-53041/ (Markdown: https://insights.sbomify.com/CVE-2026-53041/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-53041
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-53041
- OSV: https://osv.dev/vulnerability/CVE-2026-53041

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-53041/
Summaries are generated and may contain mistakes; the official description above is the record.
