# CVE-2026-10046: Out-of-bounds write in Napoca BIOS INT 0x15 E820 memory map handler (VA-13905)

> A malicious guest can trigger an out-of-bounds write in the hypervisor's BIOS handler, potentially leading to code execution or privilege escalation.

- **Severity:** High 8.5 (`CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **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:** No
- **Published:** 2 Jun 2026
- **Updated:** 2 Jun 2026
- **Also known as:** GHSA-mpc3-vg75-whww

## What is CVE-2026-10046?

CVE-2026-10046 is a high-severity memory corruption vulnerability in Bitdefender Napoca bare-metal hypervisor, published on 2 Jun 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Bitdefender Napoca bare-metal hypervisor contains an out-of-bounds write vulnerability in the BIOS INT 0x15 / E820 memory map handler, implemented in napoca/guests/bios_handlers.c. The handler computes a destination offset into the guest RealModeMemory buffer from guest-controlled ES and EDI register values without validating that the resulting address remains within the 1MB RealModeMemory allocation. A malicious guest operating in real mode can trigger the issue by invoking INT 0x15 with AX=0xE820, EDX=0x534D4150, ECX greater than or equal to 20, EBX=0, ES=0xFFFF, and EDI=0xFFFF. This can cause a write of up to 20 bytes past the end of the RealModeMemory buffer into the hypervisor heap. The product is end-of-life and unsupported when assigned.

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

## Which versions are affected by CVE-2026-10046?

It affects 1 product.


Products: Bitdefender Napoca.

## How do I fix CVE-2026-10046?

No fix has been published for CVE-2026-10046 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-10046 being exploited?

There is no known exploitation of CVE-2026-10046 in the wild and no public exploit code.

## Other vulnerabilities in Bitdefender Napoca bare-metal hypervisor

- [CVE-2026-10047](https://insights.sbomify.com/CVE-2026-10047/): Out-of-bounds write in Napoca real-mode hook handler via guest-controlled SS:SP (VA-13905) (high 8.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-10046 and fix it if it is affected.

What it is: CVE-2026-10046 is a high-severity memory corruption vulnerability in Bitdefender Napoca bare-metal hypervisor, published on 2 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-2026-10046 in the wild and no public exploit code.

Affected product: Bitdefender Napoca bare-metal hypervisor. 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-2026-10046/ (Markdown: https://insights.sbomify.com/CVE-2026-10046/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-10046
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-10046
- OSV: https://osv.dev/vulnerability/CVE-2026-10046

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-10046/
Summaries are generated and may contain mistakes; the official description above is the record.