# CVE-2026-42450: OpenColorIO vulnerable to stack buffer overflow via unbounded `sscanf %s` in Spi3D (.spi3d) LUT parser

> A stack buffer overflow in OpenColorIO allows attackers to execute arbitrary code or cause denial of service via a crafted .spi3d LUT file.

- **Severity:** High 8.4 (`CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 24 Jun 2026
- **Updated:** 24 Jun 2026
- **Also known as:** DEBIAN-CVE-2026-42450, GHSA-rxp3-rrgx-f547, UBUNTU-CVE-2026-42450, openSUSE-SU-2026:10801-1

## What is CVE-2026-42450?

CVE-2026-42450 is a high-severity memory corruption vulnerability in AcademySoftwareFoundation OpenColorIO, published on 24 Jun 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

### Official description

OpenColorIO is a color management framework for visual effects and animation. Prior to version 2.5.2, `FileFormatSpi3D.cpp:163` uses `sscanf` with `%s` into 64-byte stack buffers when parsing LUT data lines. Input comes from `lineBuffer[4096]`, so a crafted .spi3d file can overflow by ~4000 bytes on non-Windows. Version 2.5.2 fixes the issue.

Weakness: CWE-120 (Buffer Copy without Checking Size of Input)

## Which versions are affected by CVE-2026-42450?


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `OpenColorIO` | openSUSE:Tumbleweed | All versions | 2.5.2-1.1 |

## How do I fix CVE-2026-42450?

Upgrade to a fixed version.

## Is CVE-2026-42450 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-42450 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-42450 and fix it if it is affected.

What it is: CVE-2026-42450 is a high-severity memory corruption vulnerability in AcademySoftwareFoundation OpenColorIO, published on 24 Jun 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-42450 exists.

Affected product: AcademySoftwareFoundation OpenColorIO. 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-2026-42450/ (Markdown: https://insights.sbomify.com/CVE-2026-42450/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-42450
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-42450
- OSV: https://osv.dev/vulnerability/CVE-2026-42450

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-42450/
Summaries are generated and may contain mistakes; the official description above is the record.