# CVE-2026-63420: OpenImageIO: PSD RawColor indexed image out-of-bounds read in `interleave_row`

> An out-of-bounds read in OpenImageIO's PSD handling causes a crash when processing indexed images with raw color options enabled.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H`)
- **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:** 18 Sep 2026
- **Updated:** 22 Sep 2026
- **Also known as:** DEBIAN-CVE-2026-63420, GHSA-x877-h4xx-5m5j, UBUNTU-CVE-2026-63420

## What is CVE-2026-63420?

CVE-2026-63420 is a medium-severity memory corruption vulnerability in Openimageio Openimageio, published on 18 Sep 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

OpenImageIO is a toolset for reading, writing, and manipulating image files of any image file format relevant to VFX / animation. Prior to 3.0.21.0, 3.1.16.0, and 3.2.0.3-beta1, An indexed psd with transparency metadata creates fewer stored channel_buffers than the spec.nchannels value advertised by the rawcolor path. when oiio:rawcolor or psd:rawdata is enabled, psdinput::read_native_scanline() passes spec.nchannels to psdinput::interleave_row(), which indexes beyond channel_buffers, resulting in a heap out-of-bounds read and process crash. The affected implementation is identified by src/psd.imageio/psdinput.cpp, PSDInput::read_native_scanline(), PSDInput::interleave_row(), oiio:RawColor, psd:RawData, channel_buffers, and spec.nchannels, which define the relevant source path, functions, state, and trigger. This issue is fixed in versions 3.0.21.0, 3.1.16.0, and 3.2.0.3-beta1.

Weakness: CWE-129 (Improper Validation of Array Index), CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2026-63420?

It affects 1 product.


Products: Openimageio Openimageio.

## How do I fix CVE-2026-63420?

Upgrade to a fixed version.

## Is CVE-2026-63420 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-63420 exists.

## Other vulnerabilities in Openimageio Openimageio

- [CVE-2024-55192](https://insights.sbomify.com/CVE-2024-55192/): Memory corruption in n/a (critical 9.8)
- [CVE-2024-55194](https://insights.sbomify.com/CVE-2024-55194/): Memory corruption in n/a (critical 9.8)
- [CVE-2023-42299](https://insights.sbomify.com/CVE-2023-42299/): Memory corruption in n/a (critical 9.8)
- [CVE-2022-38143](https://insights.sbomify.com/CVE-2022-38143/): Memory corruption in OpenImageIO (critical 9.8)
- [CVE-2026-43908](https://insights.sbomify.com/CVE-2026-43908/): OpenImageIO: Signed integer overflow in ConvertCbYCrYToRGB leads to heap out-of-bounds write in DPX 4:2:2 decoder (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-63420 and fix it if it is affected.

What it is: CVE-2026-63420 is a medium-severity memory corruption vulnerability in Openimageio Openimageio, published on 18 Sep 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-2026-63420 exists.

Affected product: Openimageio Openimageio. 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-2026-63420/ (Markdown: https://insights.sbomify.com/CVE-2026-63420/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-63420
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-63420
- OSV: https://osv.dev/vulnerability/CVE-2026-63420

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-63420/
Summaries are generated and may contain mistakes; the official description above is the record.