CVE-2026-116501: high-severity vulnerability in IBM Qiskit SDK
Qiskit SDK C API may trigger an out of bounds write on accessing the unitary matrix with qk_circuit_inst_unitary().
Published · Updated
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18Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.4
IBM Qiskit SDK 2.4.0 through 2.6.1 could allow a local attacker to execute arbitrary code due to an out-of-bounds write caused by improper input validation when accessing a corrupted unitary matrix.
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products
IBM · Qiskit SDKRelated CVEs — IBM Qiskit SDK
In the same product, most dangerous first.
CVE-2025-2000CRITICALQiskit SDK code executionEPSS 0.8%CVE-2025-1403HIGHQiskit SDK denial of serviceEPSS 0.7%CVE-2026-19795MEDIUMQiskit SDK is vulnerable when deserializing QPY Files and may overflow the available stack space.EPSS 0.3%CVE-2026-4870HIGHQiskit SDK is vulnerable to specific functions may recurse too deeply and overflow the available stack space, when encountering certain classical expressions.EPSS 0.3%CVE-2026-116500MEDIUMUnbound Recursion in QPY deserialization can lead to denial of serviceEPSS —CVE-2026-116499HIGHArbitrary Code Execution in Qiskit SDK QPY DeserializationEPSS —