# CVE-2026-43273: ceph: supply snapshot context in ceph_zero_partial_object()


- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Fix available:** Yes
- **Published:** 6 May 2026
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2026-43273, DEBIAN-CVE-2026-43273, GHSA-fcq7-vvcv-2qg9, ROOT-OS-DEBIAN-11-CVE-2026-43273, ROOT-OS-UBUNTU-2204-CVE-2026-43273, ROOT-OS-UBUNTU-2404-CVE-2026-43273, UBUNTU-CVE-2026-43273

## What is CVE-2026-43273?

CVE-2026-43273 is a medium-severity vulnerability in Linux kernel, published on 6 May 2026. 

### Official description

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

ceph: supply snapshot context in ceph_zero_partial_object()

The ceph_zero_partial_object function was missing proper snapshot
context for its OSD write operations, which could lead to data
inconsistencies in snapshots.

Reproducer:
../src/vstart.sh --new -x --localhost --bluestore
./bin/ceph auth caps client.fs_a mds 'allow rwps fsname=a' mon 'allow r fsname=a' osd 'allow rw tag cephfs data=a'
mount -t ceph fs_a@.a=/ /mnt/mycephfs/ -o conf=./ceph.conf
dd if=/dev/urandom of=/mnt/mycephfs/foo bs=64K count=1
mkdir /mnt/mycephfs/.snap/snap1
md5sum /mnt/mycephfs/.snap/snap1/foo
fallocate -p -o 0 -l 4096 /mnt/mycephfs/foo
echo 3 > /proc/sys/vm/drop/caches
md5sum /mnt/mycephfs/.snap/snap1/foo # get different md5sum!!

## Which versions are affected by CVE-2026-43273?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-43273?

Upgrade to a fixed version.

## Is CVE-2026-43273 being exploited?

There is no known exploitation of CVE-2026-43273 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-2026-43273 and fix it if it is affected.

What it is: CVE-2026-43273 is a medium-severity vulnerability in Linux kernel, published on 6 May 2026. 
Exploitation: There is no known exploitation of CVE-2026-43273 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-2026-43273/ (Markdown: https://insights.sbomify.com/CVE-2026-43273/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-43273
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-43273
- OSV: https://osv.dev/vulnerability/CVE-2026-43273

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-43273/
Summaries are generated and may contain mistakes; the official description above is the record.