8.3
HIGH CVSS 3.1
CVE-2026-63638
OpenImageIO: Cineon invalid bit depth heap out-of-bounds write
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, A crafted cineon image can declare unsupported component bit depth 26. cineoninput::open() maps it to a 32-bit imagespec, but libcineon maps the unsupported depth to an 8-byte value, so cineoninput::read_native_scanline() causes attacker-controlled data to be written beyond the 4-byte-per-pixel caller buffer, resulting in a heap out-of-bounds write and memory corruption. The affected implementation is identified by src/cineon.imageio/cineoninput.cpp, CineonInput::open(), CineonInput::read_native_scanline(), ComponentDataSize(), bit depth 26, and ImageSpec, 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.

INFO

Published Date :

Sept. 18, 2026, 4:17 p.m.

Last Modified :

Sept. 22, 2026, 3:17 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-63638 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Openimageio openimageio
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 HIGH MITRE-CVE
CVSS 3.1 HIGH [email protected]
Solution
Update OpenImageIO to a patched version to fix heap out-of-bounds write vulnerability.
  • Update OpenImageIO to version 3.0.21.0 or later.
  • Update OpenImageIO to version 3.1.16.0 or later.
  • Update OpenImageIO to version 3.2.0.3-beta1 or later.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-63638 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-63638 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-63638 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-63638 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Sep. 22, 2026

    Action Type Old Value New Value
    Added Reference https://github.com/AcademySoftwareFoundation/OpenImageIO/security/advisories/GHSA-9hxv-jvgr-3x8g
    Added SSVC {'id': 'CVE-2026-63638', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-09-22T14:47:37.944039Z'}
  • New CVE Received by [email protected]

    Sep. 18, 2026

    Action Type Old Value New Value
    Added 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, A crafted cineon image can declare unsupported component bit depth 26. cineoninput::open() maps it to a 32-bit imagespec, but libcineon maps the unsupported depth to an 8-byte value, so cineoninput::read_native_scanline() causes attacker-controlled data to be written beyond the 4-byte-per-pixel caller buffer, resulting in a heap out-of-bounds write and memory corruption. The affected implementation is identified by src/cineon.imageio/cineoninput.cpp, CineonInput::open(), CineonInput::read_native_scanline(), ComponentDataSize(), bit depth 26, and ImageSpec, 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.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:H
    Added CWE CWE-787
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/63xxx/CVE-2026-63638.json">CVE-2026-63638</a>
    Added Reference https://github.com/AcademySoftwareFoundation/OpenImageIO/commit/6f2b2e85b3b3933ccc5a46303d5535f99bfa39fb
    Added Reference https://github.com/AcademySoftwareFoundation/OpenImageIO/pull/5283
    Added Reference https://github.com/AcademySoftwareFoundation/OpenImageIO/releases/tag/v3.0.21.0
    Added Reference https://github.com/AcademySoftwareFoundation/OpenImageIO/releases/tag/v3.1.16.0
    Added Reference https://github.com/AcademySoftwareFoundation/OpenImageIO/security/advisories/GHSA-9hxv-jvgr-3x8g
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.