# CVE-2026-68433: libceph: bound get_version reply decode to front len

> A truncated reply in libceph can cause an uninitialized memory read, potentially disclosing stale kernel memory to an attacker.

- **Severity:** High 8.6 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 12 Aug 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2026-68433, DEBIAN-CVE-2026-68433, GHSA-w6pj-fv9f-22wf, UBUNTU-CVE-2026-68433

## What is CVE-2026-68433?

CVE-2026-68433 is a high-severity vulnerability in Linux, published on 12 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

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

libceph: bound get_version reply decode to front len

handle_get_version_reply() uses msg->front_alloc_len as the decode
boundary for MON_GET_VERSION_REPLY.  That is the size of the reused
reply buffer, not the number of bytes actually received.

A truncated reply can therefore pass ceph_decode_need() and decode the
second u64 from stale tail bytes left in the buffer by an earlier
message, causing an uninitialized memory read.

Use msg->front.iov_len as the receive-side decode boundary, matching
other libceph reply handlers and limiting decoding to the bytes that
were actually read from the wire.

Weakness: CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2026-68433?


## How do I fix CVE-2026-68433?

Apply the vendor's patch.

## Is CVE-2026-68433 being exploited?

There is no known exploitation of CVE-2026-68433 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-68433 and fix it if it is affected.

What it is: CVE-2026-68433 is a high-severity vulnerability in Linux, published on 12 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-68433 in the wild and no public exploit code.

Affected product: Linux. 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-2026-68433/ (Markdown: https://insights.sbomify.com/CVE-2026-68433/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-68433
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-68433
- OSV: https://osv.dev/vulnerability/CVE-2026-68433

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-68433/
Summaries are generated and may contain mistakes; the official description above is the record.