# CVE-2026-80693: idpf: bound interrupt-vector register fill to the allocated array

> A buffer overflow in the Linux kernel idpf driver allows a malicious control plane to write out of bounds, potentially leading to code execution or privilege escalation.

- **Severity:** Critical 9.3 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 28 Aug 2026
- **Updated:** 21 Oct 2026
- **Also known as:** BELL-CVE-2026-80693, DEBIAN-CVE-2026-80693, GHSA-h68f-vq23-xjh9, UBUNTU-CVE-2026-80693

## What is CVE-2026-80693?

CVE-2026-80693 is a critical memory corruption vulnerability in Linux, published on 28 Aug 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:

idpf: bound interrupt-vector register fill to the allocated array

idpf_get_reg_intr_vecs() fills the caller-allocated reg_vals[] array from
the VIRTCHNL2_OP_ALLOC_VECTORS reply in adapter->req_vec_chunks, bounding
its inner loop only by the per-chunk num_vectors. The array is sized
separately: idpf_intr_reg_init() allocates
kzalloc_objs(struct idpf_vec_regs, total_vecs) from
caps.num_allocated_vectors and only checks the returned count after the
fill. The sum of per-chunk num_vectors is never reconciled against
total_vecs, so a reply with a small num_allocated_vectors but chunks
summing higher writes past the end of reg_vals[].

Impact: a control plane (a PF or hypervisor device model) that returns a
VIRTCHNL2_OP_ALLOC_VECTORS reply whose per-chunk num_vectors sum exceeds
num_allocated_vectors writes struct idpf_vec_regs entries past the end of
the reg_vals kmalloc allocation (KASAN slab-out-of-bounds write).

Bound the fill loop to the array capacity passed in by the callers,
mirroring the sibling idpf_vport_get_q_reg(). The existing
num_regs < num_vecs check then rejects an undersized reply without the
out-of-bounds write happening first.

## Which versions are affected by CVE-2026-80693?


## How do I fix CVE-2026-80693?

Apply the vendor's patch.

## Is CVE-2026-80693 being exploited?

There is no known exploitation of CVE-2026-80693 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-80693 and fix it if it is affected.

What it is: CVE-2026-80693 is a critical memory corruption vulnerability in Linux, published on 28 Aug 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-2026-80693 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-2026-80693/ (Markdown: https://insights.sbomify.com/CVE-2026-80693/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-80693
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-80693
- OSV: https://osv.dev/vulnerability/CVE-2026-80693

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-80693/
Summaries are generated and may contain mistakes; the official description above is the record.