Heap-based buffer overflow in onnx - CVE-2026-63632
Published: July 3, 2026 / Updated: August 19, 2026
Vulnerability identifier: #VU136855
CSH Severity: Low
CVSS v4: 4.6 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-63632
CWE-ID: CWE-122
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to disclose sensitive information or cause a denial of service.
The vulnerability exists due to a heap-based buffer overflow in Gemm_7_6::adapt_gemm_7_6() when processing a crafted model during version conversion. A remote attacker can trick the victim into processing a specially crafted model to disclose sensitive information or cause a denial of service.
User interaction is required to process the crafted model through onnx.version_converter.convert_version(model, 6) during opset downgrade from 7 to 6.
Affected software
onnx
How to mitigate CVE-2026-63632
Install security update from vendor's website.
onnx - update to 1.22.0