{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-23557", "assignerOrgId": "23aa2041-22e1-471f-9209-9b7396fa234f", "state": "PUBLISHED", "assignerShortName": "XEN", "dateReserved": "2026-01-14T13:07:36.961Z", "datePublished": "2026-05-19T12:49:42.202Z", "dateUpdated": "2026-05-19T14:42:45.464Z"}, "containers": {"cna": {"title": "Xenstored DoS via XS_RESET_WATCHES command", "datePublic": "2026-04-28T12:00:00.000Z", "descriptions": [{"lang": "en", "value": "Any guest can cause xenstored to crash by issuing a XS_RESET_WATCHES\ncommand within a transaction due to an assert() triggering.\n\nIn case xenstored was built with NDEBUG #defined nothing bad will\nhappen, as assert() is doing nothing in this case. Note that the\ndefault is not to define NDEBUG for xenstored builds even in release\nbuilds of Xen."}], "impacts": [{"descriptions": [{"lang": "en", "value": "Any unprivileged domain can cause xenstored to crash, causing a\nDoS (denial of service) for any Xenstore action. This will result\nin an inability to perform further domain administration on the host."}]}], "affected": [{"defaultStatus": "unknown", "product": "Xen", "vendor": "Xen", "versions": [{"status": "unknown", "version": "consult Xen advisory XSA-484"}]}], "configurations": [{"lang": "en", "value": "All Xen systems from Xen 4.2 onwards are vulnerable. Systems up to\nXen 4.1 are not vulnerable.\n\nSystems using the C variant of xenstored or xenstore-stubdom built\nwithout NDEBUG are vulnerable. Systems using the OCaml variant of\nXenstore (oxenstored), or the C variant (xenstored or xenstore-stubdom)\nbuilt with NDEBUG defined are not vulnerable."}], "workarounds": [{"lang": "en", "value": "There is no known mitigation available."}], "credits": [{"lang": "en", "type": "finder", "value": "This issue was discovered by Andrii Sultanov of Vates."}], "references": [{"url": "https://xenbits.xenproject.org/xsa/advisory-484.html"}], "providerMetadata": {"orgId": "23aa2041-22e1-471f-9209-9b7396fa234f", "shortName": "XEN", "dateUpdated": "2026-05-19T12:49:42.202Z"}}, "adp": [{"title": "CVE Program Container", "references": [{"url": "http://www.openwall.com/lists/oss-security/2026/04/28/11"}, {"url": "http://xenbits.xen.org/xsa/advisory-484.html"}], "providerMetadata": {"orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2026-05-19T13:06:41.611Z"}}, {"problemTypes": [{"descriptions": [{"type": "CWE", "cweId": "CWE-617", "lang": "en", "description": "CWE-617 Reachable Assertion"}]}], "metrics": [{"cvssV3_1": {"scope": "CHANGED", "version": "3.1", "baseScore": 6.5, "attackVector": "LOCAL", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}}, {"other": {"type": "ssvc", "content": {"timestamp": "2026-05-19T14:42:12.994792Z", "id": "CVE-2026-23557", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "role": "CISA Coordinator", "version": "2.0.3"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-05-19T14:42:45.464Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CVE Program Container", "references": [{"url": "http://www.openwall.com/lists/oss-security/2026/04/28/11"}, {"url": "http://xenbits.xen.org/xsa/advisory-484.html"}], "providerMetadata": {"orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2026-05-19T13:06:41.611Z"}}, {"title": "CISA ADP Vulnrichment", "metrics": [{"cvssV3_1": {"scope": "CHANGED", "version": "3.1", "baseScore": 6.5, "attackVector": "LOCAL", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}}, {"other": {"type": "ssvc", "content": {"id": "CVE-2026-23557", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-05-19T14:42:12.994792Z"}}}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-617", "description": "CWE-617 Reachable Assertion"}]}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-05-19T14:41:23.482Z"}}], "cna": {"title": "Xenstored DoS via XS_RESET_WATCHES command", "credits": [{"lang": "en", "type": "finder", "value": "This issue was discovered by Andrii Sultanov of Vates."}], "impacts": [{"descriptions": [{"lang": "en", "value": "Any unprivileged domain can cause xenstored to crash, causing a\nDoS (denial of service) for any Xenstore action. This will result\nin an inability to perform further domain administration on the host."}]}], "affected": [{"vendor": "Xen", "product": "Xen", "versions": [{"status": "unknown", "version": "consult Xen advisory XSA-484"}], "defaultStatus": "unknown"}], "datePublic": "2026-04-28T12:00:00.000Z", "references": [{"url": "https://xenbits.xenproject.org/xsa/advisory-484.html"}], "workarounds": [{"lang": "en", "value": "There is no known mitigation available."}], "descriptions": [{"lang": "en", "value": "Any guest can cause xenstored to crash by issuing a XS_RESET_WATCHES\ncommand within a transaction due to an assert() triggering.\n\nIn case xenstored was built with NDEBUG #defined nothing bad will\nhappen, as assert() is doing nothing in this case. Note that the\ndefault is not to define NDEBUG for xenstored builds even in release\nbuilds of Xen."}], "configurations": [{"lang": "en", "value": "All Xen systems from Xen 4.2 onwards are vulnerable. Systems up to\nXen 4.1 are not vulnerable.\n\nSystems using the C variant of xenstored or xenstore-stubdom built\nwithout NDEBUG are vulnerable. Systems using the OCaml variant of\nXenstore (oxenstored), or the C variant (xenstored or xenstore-stubdom)\nbuilt with NDEBUG defined are not vulnerable."}], "providerMetadata": {"orgId": "23aa2041-22e1-471f-9209-9b7396fa234f", "shortName": "XEN", "dateUpdated": "2026-05-19T12:49:42.202Z"}}}, "cveMetadata": {"cveId": "CVE-2026-23557", "state": "PUBLISHED", "dateUpdated": "2026-05-19T14:42:45.464Z", "dateReserved": "2026-01-14T13:07:36.961Z", "assignerOrgId": "23aa2041-22e1-471f-9209-9b7396fa234f", "datePublished": "2026-05-19T12:49:42.202Z", "assignerShortName": "XEN"}, "dataVersion": "5.2"}

{"configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:xen:xen:*:*:*:*:*:*:*:*", "matchCriteriaId": "37DFEBDB-42A9-4A8C-A040-CC08782EF553", "versionStartIncluding": "4.2.0", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Any guest can cause xenstored to crash by issuing a XS_RESET_WATCHES\ncommand within a transaction due to an assert() triggering.\n\nIn case xenstored was built with NDEBUG #defined nothing bad will\nhappen, as assert() is doing nothing in this case. Note that the\ndefault is not to define NDEBUG for xenstored builds even in release\nbuilds of Xen."}], "id": "CVE-2026-23557", "lastModified": "2026-05-19T18:56:35.513", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 6.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "CHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 2.0, "impactScore": 4.0, "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}, "published": "2026-05-19T14:16:38.817", "references": [{"source": "security@xen.org", "tags": ["Patch", "Vendor Advisory"], "url": "https://xenbits.xenproject.org/xsa/advisory-484.html"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Mailing List", "Patch", "Third Party Advisory"], "url": "http://www.openwall.com/lists/oss-security/2026/04/28/11"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch", "Vendor Advisory"], "url": "http://xenbits.xen.org/xsa/advisory-484.html"}], "sourceIdentifier": "security@xen.org", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-617"}], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}

{}