{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-19795", "assignerOrgId": "9a959283-ebb5-44b6-b705-dcc2bbced522", "state": "PUBLISHED", "assignerShortName": "ibm", "dateReserved": "2026-08-13T19:40:18.000Z", "datePublished": "2026-09-03T19:56:03.172Z", "dateUpdated": "2026-09-03T19:56:03.172Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "9a959283-ebb5-44b6-b705-dcc2bbced522", "shortName": "ibm", "dateUpdated": "2026-09-03T19:56:03.172Z"}, "title": "Qiskit SDK is vulnerable when deserializing QPY Files and may overflow the available stack space.", "problemTypes": [{"descriptions": [{"lang": "en", "cweId": "CWE-502", "description": "CWE-502 Deserialization of Untrusted Data", "type": "CWE"}]}], "affected": [{"vendor": "IBM", "product": "Qiskit SDK", "versions": [{"status": "affected", "version": "2.1.0", "lessThanOrEqual": "2.5.1", "versionType": "semver"}], "cpes": ["cpe:2.3:a:ibm:qiskit_sdk:2.1.0:*:*:*:*:*:*:*", "cpe:2.3:a:ibm:qiskit_sdk:2.5.1:*:*:*:*:*:*:*"]}], "descriptions": [{"lang": "en", "value": "IBM Qiskit SDK 2.1.0 through 2.5.1 could allow a local attacker to cause a denial of service due to improper handling of a specially crafted object during deserialization. A malicious QPY payload can trigger a segmentation fault, causing the application to crash when deserializing untrusted input.", "supportingMedia": [{"type": "text/html", "base64": false, "value": "<p>IBM Qiskit SDK 2.1.0 through 2.5.1 could allow a local attacker to cause a denial of service due to improper handling of a specially crafted object during deserialization. A malicious QPY payload can trigger a segmentation fault, causing the application to crash when deserializing untrusted input.</p>"}]}], "references": [{"url": "https://www.ibm.com/support/pages/node/7285932", "tags": ["vendor-advisory", "patch"]}], "metrics": [{"format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}], "cvssV3_1": {"version": "3.1", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH", "baseSeverity": "MEDIUM", "baseScore": 6.2, "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}}], "workarounds": [{"lang": "en", "value": "Workarounds/Mitigation guidance:\n\nNone", "supportingMedia": [{"type": "text/html", "base64": false, "value": "<p><strong>Workarounds/Mitigation guidance</strong>:</p><p><br/>None</p><p></p>"}]}], "solutions": [{"lang": "en", "value": "Remediation/Fixes guidance:\nThe issue is addressed in Qiskit versions v2.5.2. This version is patched to prevent the stack overflow by no longer evaluating the expression tree for ParameterExpression objects recursively.\n\nProduct(s)Version(s) number and/or range Remediation/Fix/Instructions<Qiskit SDK - qiskit.qpy.load() function>v2.5.2Upgrade to the patched versions: qiskit v2.5.2.", "supportingMedia": [{"type": "text/html", "base64": false, "value": "<p><strong>Remediation/Fixes guidance</strong>:</p><p>The issue is addressed in Qiskit versions v2.5.2. This version is patched to prevent the stack overflow by no longer evaluating the expression tree for ParameterExpression objects recursively.<br/><br/></p><div><table><tbody><tr><td><strong>Product(s)</strong></td><td><strong>Version(s) number and/or range\u00a0</strong></td><td><strong>Remediation/Fix/Instructions</strong></td></tr><tr><td>&lt;Qiskit SDK - qiskit.qpy.load() function&gt;</td><td>v2.5.2</td><td><pre>Upgrade to the patched versions: qiskit v2.5.2.</pre></td></tr></tbody></table></div><p></p><p></p>"}]}], "credits": [{"lang": "en", "value": "Issue discovered by Matthew Treinish (IBM) and Takashi Imamichi (IBM)", "type": "finder"}]}}}

{}

{"affected": [{"affectedData": [{"cpes": ["cpe:2.3:a:ibm:qiskit_sdk:2.1.0:*:*:*:*:*:*:*", "cpe:2.3:a:ibm:qiskit_sdk:2.5.1:*:*:*:*:*:*:*"], "product": "Qiskit SDK", "vendor": "IBM", "versions": [{"lessThanOrEqual": "2.5.1", "status": "affected", "version": "2.1.0", "versionType": "semver"}]}], "source": "psirt@us.ibm.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "IBM Qiskit SDK 2.1.0 through 2.5.1 could allow a local attacker to cause a denial of service due to improper handling of a specially crafted object during deserialization. A malicious QPY payload can trigger a segmentation fault, causing the application to crash when deserializing untrusted input."}], "id": "CVE-2026-19795", "lastModified": "2026-09-03T20:17:19.790", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 6.2, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 2.5, "impactScore": 3.6, "source": "psirt@us.ibm.com", "type": "Primary"}]}, "published": "2026-09-03T20:17:19.790", "references": [{"source": "psirt@us.ibm.com", "url": "https://www.ibm.com/support/pages/node/7285932"}], "sourceIdentifier": "psirt@us.ibm.com", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-502"}], "source": "psirt@us.ibm.com", "type": "Primary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[2.1.0,2.5.1]"}}], "enrichment": {"confidence": 95.0, "confidence_source": "inferred", "scores": [{"score": 95.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Qiskit SDK", "source": "cna", "vendor": "IBM"}, "product": "qiskit_sdk", "vendor": "ibm"}], "created": "2026-09-03T21:30:05.624219+00:00", "updated": "2026-09-03T21:45:09.662149+00:00", "vendors": ["ibm", "ibm$PRODUCT$qiskit_sdk"]}