{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-31786", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-03-09T15:48:24.141Z", "datePublished": "2026-04-30T10:31:28.293Z", "dateUpdated": "2026-04-30T10:39:32.708Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-04-30T10:31:28.293Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBuffer overflow in drivers/xen/sys-hypervisor.c\n\nThe build id returned by HYPERVISOR_xen_version(XENVER_build_id) is\nneither NUL terminated nor a string.\n\nThe first causes a buffer overflow as sprintf in buildid_show will\nread and copy till it finds a NUL.\n\n00000000 f4 91 51 f4 dd 38 9e 9d 65 47 52 eb 10 71 db 50 |..Q..8..eGR..q.P|\n00000010 b9 a8 01 42 6f 2e 32 |...Bo.2|\n00000017\n\nSo use a memcpy instead of sprintf to have the correct value:\n\n00000000 f4 91 51 f4 dd 00 9e 9d 65 47 52 eb 10 71 db 50 |..Q.....eGR..q.P|\n00000010 b9 a8 01 42 |...B|\n00000014\n\n(the above have a hack to embed a zero inside and check it's\nreturned correctly).\n\nThis is XSA-485 / CVE-2026-31786"}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/xen/sys-hypervisor.c"], "versions": [{"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "e3af585e1728c917682b6a3de9a69b41fb9194d4", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "8288d031a01dbacfde3fc643f7be3d23504de64d", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "f458ba102da97fafca106327086fc95f3fc764cb", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "4b4defd2fce3f966c25adabf46644a85558f1169", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "5c5ff7c7bd15bb536f44b10b3fb5b8408f344d0a", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "d5f59216650c51e5e3fcb7517c825bc8047f60ef", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "52cecff98bda2c51eed1c6ce9d21c5d6268fb19d", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/xen/sys-hypervisor.c"], "versions": [{"version": "5.10.254", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.15.204", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.170", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.137", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.85", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.26", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.0.3", "lessThanOrEqual": "7.0.*", "status": "unaffected", "versionType": "semver"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "5.10.254"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "5.15.204"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.1.170"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.6.137"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.12.85"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.18.26"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "7.0.3"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/e3af585e1728c917682b6a3de9a69b41fb9194d4"}, {"url": "https://git.kernel.org/stable/c/8288d031a01dbacfde3fc643f7be3d23504de64d"}, {"url": "https://git.kernel.org/stable/c/f458ba102da97fafca106327086fc95f3fc764cb"}, {"url": "https://git.kernel.org/stable/c/4b4defd2fce3f966c25adabf46644a85558f1169"}, {"url": "https://git.kernel.org/stable/c/5c5ff7c7bd15bb536f44b10b3fb5b8408f344d0a"}, {"url": "https://git.kernel.org/stable/c/d5f59216650c51e5e3fcb7517c825bc8047f60ef"}, {"url": "https://git.kernel.org/stable/c/52cecff98bda2c51eed1c6ce9d21c5d6268fb19d"}], "title": "Buffer overflow in drivers/xen/sys-hypervisor.c", "x_generator": {"engine": "bippy-1.2.0"}}, "adp": [{"title": "CVE Program Container", "references": [{"url": "http://www.openwall.com/lists/oss-security/2026/04/28/12"}, {"url": "http://xenbits.xen.org/xsa/advisory-485.html"}], "providerMetadata": {"orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2026-04-30T10:39:32.708Z"}}]}}

{}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBuffer overflow in drivers/xen/sys-hypervisor.c\n\nThe build id returned by HYPERVISOR_xen_version(XENVER_build_id) is\nneither NUL terminated nor a string.\n\nThe first causes a buffer overflow as sprintf in buildid_show will\nread and copy till it finds a NUL.\n\n00000000 f4 91 51 f4 dd 38 9e 9d 65 47 52 eb 10 71 db 50 |..Q..8..eGR..q.P|\n00000010 b9 a8 01 42 6f 2e 32 |...Bo.2|\n00000017\n\nSo use a memcpy instead of sprintf to have the correct value:\n\n00000000 f4 91 51 f4 dd 00 9e 9d 65 47 52 eb 10 71 db 50 |..Q.....eGR..q.P|\n00000010 b9 a8 01 42 |...B|\n00000014\n\n(the above have a hack to embed a zero inside and check it's\nreturned correctly).\n\nThis is XSA-485 / CVE-2026-31786"}], "id": "CVE-2026-31786", "lastModified": "2026-04-30T17:11:25.563", "metrics": {}, "published": "2026-04-30T11:16:20.967", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/4b4defd2fce3f966c25adabf46644a85558f1169"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/52cecff98bda2c51eed1c6ce9d21c5d6268fb19d"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/5c5ff7c7bd15bb536f44b10b3fb5b8408f344d0a"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/8288d031a01dbacfde3fc643f7be3d23504de64d"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/d5f59216650c51e5e3fcb7517c825bc8047f60ef"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/e3af585e1728c917682b6a3de9a69b41fb9194d4"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/f458ba102da97fafca106327086fc95f3fc764cb"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "url": "http://www.openwall.com/lists/oss-security/2026/04/28/12"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "url": "http://xenbits.xen.org/xsa/advisory-485.html"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Awaiting Analysis"}

{"bugzilla": {"description": "kernel: Buffer overflow in drivers/xen/sys-hypervisor.c", "id": "2464096", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2464096"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.0", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "status": "draft"}, "cwe": "CWE-170", "details": ["A flaw was found in the Linux kernel. A buffer overflow vulnerability exists in the Xen hypervisor driver (`drivers/xen/sys-hypervisor.c`). This flaw occurs because the `HYPERVISOR_xen_version(XENVER_build_id)` function returns a build ID that is not properly null-terminated. When the `buildid_show` function attempts to process this non-null-terminated string using `sprintf`, it can read and copy beyond the intended buffer boundary, potentially leading to a denial of service or other unspecified impacts."], "name": "CVE-2026-31786", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Under investigation", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-04-30T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-31786\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-31786\nhttps://lore.kernel.org/linux-cve-announce/2026043031-CVE-2026-31786-826a@gregkh/T"], "threat_severity": "Important"}