CVE-2026-80662

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-80662", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-26T14:34:25.781Z", "datePublished": "2026-08-28T06:49:06.277Z", "dateUpdated": "2026-10-21T12:46:49.254Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-21T12:46:49.254Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncxl: Fix CXL_HEADERLOG_SIZE to match RAS Capability size\n\nThe CXL r4.0 8.2.4.17.7 RAS Capability Structure has total length 0x58\nbytes (CXL_RAS_CAPABILITY_LENGTH); the Header Log occupies the trailing\n64 bytes at offset 0x18. CXL_HEADERLOG_SIZE was defined as SZ_512,\neight times the actual on-device size.\n\nheader_log_copy() reads CXL_HEADERLOG_SIZE_U32 (128) dwords from the\nRAS capability iomap, overrunning the 88-byte mapping by 448 bytes.\nThe cxl_aer_uncorrectable_error trace event memcpy()s CXL_HEADERLOG_SIZE\n(512) bytes from its source. For the CPER caller the source is\nstruct cxl_ras_capability_regs::header_log[16] (64 bytes) embedded in a\nstack-local cxl_cper_prot_err_work_data, so the memcpy reads 448 bytes\nof kernel stack into the trace event ring buffer where userspace can\nread it via tracefs.\n\nSet CXL_HEADERLOG_SIZE to 64 and derive CXL_HEADERLOG_SIZE_U32 from it,\nbringing all iomap readers into agreement on 16 dwords. Userspace tools\nsuch as rasdaemon have grown a dependency on the buggy 512-byte (128 u32)\nheader_log layout in the cxl_aer_uncorrectable_error trace event. Add\nCXL_HEADERLOG_TRACE_SIZE_U32 = 128 and use it for the trace event\n__array and its memcpy to preserve that ABI. Both callers now pass a\nzero-filled u32[CXL_HEADERLOG_TRACE_SIZE_U32] staging buffer with only\nthe first CXL_HEADERLOG_SIZE_U32 (16) entries populated from hardware;\nthe remaining 112 u32s are zero-padded, keeping the 512-byte trace ring\nbuffer layout intact.\n\n[ dj: Replaced 64 with SZ_64 per RichardC ]"}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H", "baseScore": 7.1, "baseSeverity": "HIGH"}, "scenarios": [{"lang": "en", "value": "AV:L - The bug is only reached in kernel CXL RAS error handling (cxl_handle_ras via PCI AER cxl_error_detected, and CPER paths cxl_cper_post_prot_err/extlog_cxl_cper_handle_prot_err). Disclosure requires reading tracefs; there is no network, adjacent-radio, or direct physical-bus syscall entry to the vulnerable memcpy/readl sites.\nAC:L - With CAP_SYS_ADMIN, ACPI/CXL EINJ via debugfs einj_inject deterministically injects uncorrectable CXL protocol errors that traverse cxl_cper_handle_prot_err/cxl_handle_ras. Without root, a tracing-group member on CXL servers running rasdaemon can reliably capture the leak whenever organic uncorrectable RAS events occur.\nPR:L - Exploitation requires reading cxl_aer_uncorrectable_error data from tracefs (TRACE_MODE_READ 0440), routinely granted to tracing-group/rasdaemon service accounts on CXL/RAS deployments. Triggering on demand uses debugfs EINJ (root) or natural hardware errors; no init-namespace-only capability beyond tracefs DAC is needed for the stack leak.\nUI:N - Once CXL tracepoints are enabled (as rasdaemon does automatically), uncorrectable RAS/CPER processing copies the overlong header_log during kernel error handling. No victim mount, login, or interactive action is required beyond the attacker (or environment) having tracefs access when an error fires.\nS:U - The flaw leaks kernel stack/MMIO data into the trace ring buffer within the host kernel. Impact stays in the same OS security authority (local privilege/information gain) and does not cross guest/host, IOMMU, or container hardware trust boundaries.\nC:H - TP_fast_assign memcpy() copies 512 bytes from a 64-byte ras_cap.header_log on the stack, leaking 448 bytes of kernel stack into tracefs. header_log_copy() also readl()s 128 dwords from an 88-byte RAS iomap, an out-of-bounds read of adjacent MMIO/device memory.\nI:N - Both failure modes are out-of-bounds reads only (stack and MMIO). The trace event stores leaked bytes in the ring buffer but does not corrupt attacker-controlled memory or provide a direct arbitrary-write primitive.\nA:H - header_log_copy() performs 448 bytes of MMIO reads past the devm_ioremap() RAS window (0x58 bytes), which can provoke CPU/MMU faults or platform errors on out-of-range readl(). Uncorrectable-error handling itself can disable CXL.mem devices and force resets, impacting availability."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/cxl/core/ras.c", "drivers/cxl/core/trace.h", "drivers/cxl/cxl.h"], "versions": [{"version": "2905cb5236cba63a5dc8a83752dcc31f3cc819f9", "lessThan": "d031617045dc743764ea574432e5c2a3757b4e57", "status": "affected", "versionType": "git"}, {"version": "2905cb5236cba63a5dc8a83752dcc31f3cc819f9", "lessThan": "e3e8f3b760bcf6a4b3aec412015b74b578729006", "status": "affected", "versionType": "git"}, {"version": "2905cb5236cba63a5dc8a83752dcc31f3cc819f9", "lessThan": "6fc1919a6f2ed541484dd1f6cd93374044f8fd3d", "status": "affected", "versionType": "git"}, {"version": "2905cb5236cba63a5dc8a83752dcc31f3cc819f9", "lessThan": "fc5eb0962a5e50d64e711817cc24d67df2d90528", "status": "affected", "versionType": "git"}, {"version": "2905cb5236cba63a5dc8a83752dcc31f3cc819f9", "lessThan": "c268f949e219f9e179558e836f457f6c5fbec416", "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/cxl/core/ras.c", "drivers/cxl/core/trace.h", "drivers/cxl/cxl.h"], "versions": [{"version": "6.2", "status": "affected"}, {"version": "0", "lessThan": "6.2", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.160", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.114", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.42", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.1.5", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.2", "versionEndExcluding": "6.6.160"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.2", "versionEndExcluding": "6.12.114"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.2", "versionEndExcluding": "6.18.42"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.2", "versionEndExcluding": "7.1.5"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.2", "versionEndExcluding": "7.2"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/d031617045dc743764ea574432e5c2a3757b4e57"}, {"url": "https://git.kernel.org/stable/c/e3e8f3b760bcf6a4b3aec412015b74b578729006"}, {"url": "https://git.kernel.org/stable/c/6fc1919a6f2ed541484dd1f6cd93374044f8fd3d"}, {"url": "https://git.kernel.org/stable/c/fc5eb0962a5e50d64e711817cc24d67df2d90528"}, {"url": "https://git.kernel.org/stable/c/c268f949e219f9e179558e836f457f6c5fbec416"}], "title": "cxl: Fix CXL_HEADERLOG_SIZE to match RAS Capability size", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["drivers/cxl/core/ras.c", "drivers/cxl/core/trace.h", "drivers/cxl/cxl.h"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "d031617045dc743764ea574432e5c2a3757b4e57", "status": "affected", "version": "2905cb5236cba63a5dc8a83752dcc31f3cc819f9", "versionType": "git"}, {"lessThan": "e3e8f3b760bcf6a4b3aec412015b74b578729006", "status": "affected", "version": "2905cb5236cba63a5dc8a83752dcc31f3cc819f9", "versionType": "git"}, {"lessThan": "6fc1919a6f2ed541484dd1f6cd93374044f8fd3d", "status": "affected", "version": "2905cb5236cba63a5dc8a83752dcc31f3cc819f9", "versionType": "git"}, {"lessThan": "fc5eb0962a5e50d64e711817cc24d67df2d90528", "status": "affected", "version": "2905cb5236cba63a5dc8a83752dcc31f3cc819f9", "versionType": "git"}, {"lessThan": "c268f949e219f9e179558e836f457f6c5fbec416", "status": "affected", "version": "2905cb5236cba63a5dc8a83752dcc31f3cc819f9", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["drivers/cxl/core/ras.c", "drivers/cxl/core/trace.h", "drivers/cxl/cxl.h"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "6.2"}, {"lessThan": "6.2", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.160", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.114", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.42", "versionType": "semver"}, {"lessThanOrEqual": "7.1.*", "status": "unaffected", "version": "7.1.5", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.2", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncxl: Fix CXL_HEADERLOG_SIZE to match RAS Capability size\n\nThe CXL r4.0 8.2.4.17.7 RAS Capability Structure has total length 0x58\nbytes (CXL_RAS_CAPABILITY_LENGTH); the Header Log occupies the trailing\n64 bytes at offset 0x18. CXL_HEADERLOG_SIZE was defined as SZ_512,\neight times the actual on-device size.\n\nheader_log_copy() reads CXL_HEADERLOG_SIZE_U32 (128) dwords from the\nRAS capability iomap, overrunning the 88-byte mapping by 448 bytes.\nThe cxl_aer_uncorrectable_error trace event memcpy()s CXL_HEADERLOG_SIZE\n(512) bytes from its source. For the CPER caller the source is\nstruct cxl_ras_capability_regs::header_log[16] (64 bytes) embedded in a\nstack-local cxl_cper_prot_err_work_data, so the memcpy reads 448 bytes\nof kernel stack into the trace event ring buffer where userspace can\nread it via tracefs.\n\nSet CXL_HEADERLOG_SIZE to 64 and derive CXL_HEADERLOG_SIZE_U32 from it,\nbringing all iomap readers into agreement on 16 dwords. Userspace tools\nsuch as rasdaemon have grown a dependency on the buggy 512-byte (128 u32)\nheader_log layout in the cxl_aer_uncorrectable_error trace event. Add\nCXL_HEADERLOG_TRACE_SIZE_U32 = 128 and use it for the trace event\n__array and its memcpy to preserve that ABI. Both callers now pass a\nzero-filled u32[CXL_HEADERLOG_TRACE_SIZE_U32] staging buffer with only\nthe first CXL_HEADERLOG_SIZE_U32 (16) entries populated from hardware;\nthe remaining 112 u32s are zero-padded, keeping the 512-byte trace ring\nbuffer layout intact.\n\n[ dj: Replaced 64 with SZ_64 per RichardC ]"}], "id": "CVE-2026-80662", "lastModified": "2026-10-21T13:19:57.557", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.1, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.2, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}]}, "published": "2026-08-28T08:16:51.397", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/6fc1919a6f2ed541484dd1f6cd93374044f8fd3d"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/c268f949e219f9e179558e836f457f6c5fbec416"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/d031617045dc743764ea574432e5c2a3757b4e57"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/e3e8f3b760bcf6a4b3aec412015b74b578729006"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/fc5eb0962a5e50d64e711817cc24d67df2d90528"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: cxl: Fix CXL_HEADERLOG_SIZE to match RAS Capability size", "id": "2525422", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2525422"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.5", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-125", "details": ["In the Linux kernel, the following vulnerability has been resolved:\ncxl: Fix CXL_HEADERLOG_SIZE to match RAS Capability size\nThe CXL r4.0 8.2.4.17.7 RAS Capability Structure has total length 0x58\nbytes (CXL_RAS_CAPABILITY_LENGTH); the Header Log occupies the trailing\n64 bytes at offset 0x18. CXL_HEADERLOG_SIZE was defined as SZ_512,\neight times the actual on-device size.\nheader_log_copy() reads CXL_HEADERLOG_SIZE_U32 (128) dwords from the\nRAS capability iomap, overrunning the 88-byte mapping by 448 bytes.\nThe cxl_aer_uncorrectable_error trace event memcpy()s CXL_HEADERLOG_SIZE\n(512) bytes from its source. For the CPER caller the source is\nstruct cxl_ras_capability_regs::header_log[16] (64 bytes) embedded in a\nstack-local cxl_cper_prot_err_work_data, so the memcpy reads 448 bytes\nof kernel stack into the trace event ring buffer where userspace can\nread it via tracefs.\nSet CXL_HEADERLOG_SIZE to 64 and derive CXL_HEADERLOG_SIZE_U32 from it,\nbringing all iomap readers into agreement on 16 dwords. Userspace tools\nsuch as rasdaemon have grown a dependency on the buggy 512-byte (128 u32)\nheader_log layout in the cxl_aer_uncorrectable_error trace event. Add\nCXL_HEADERLOG_TRACE_SIZE_U32 = 128 and use it for the trace event\n__array and its memcpy to preserve that ABI. Both callers now pass a\nzero-filled u32[CXL_HEADERLOG_TRACE_SIZE_U32] staging buffer with only\nthe first CXL_HEADERLOG_SIZE_U32 (16) entries populated from hardware;\nthe remaining 112 u32s are zero-padded, keeping the 512-byte trace ring\nbuffer layout intact.\n[ dj: Replaced 64 with SZ_64 per RichardC ]", "A flaw was found in the Linux kernel's Compute Express Link (CXL) subsystem. An incorrect definition of the CXL_HEADERLOG_SIZE led to an out-of-bounds read when processing RAS capability structures. This vulnerability allows a local attacker to read sensitive kernel stack memory, potentially leading to information disclosure."], "name": "CVE-2026-80662", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-08-28T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-80662\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-80662\nhttps://lore.kernel.org/linux-cve-announce/2026082846-CVE-2026-80662-9cad@gregkh/T"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[2905cb5236cba63a5dc8a83752dcc31f3cc819f9,6fc1919a6f2ed541484dd1f6cd93374044f8fd3d)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[2905cb5236cba63a5dc8a83752dcc31f3cc819f9,fc5eb0962a5e50d64e711817cc24d67df2d90528)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[2905cb5236cba63a5dc8a83752dcc31f3cc819f9,c268f949e219f9e179558e836f457f6c5fbec416)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "6.2"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,6.2)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[6.18.42,6.18.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.1.5,7.1.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.2, *)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-08-28T11:45:04.209480+00:00", "updated": "2026-08-31T16:00:06.138167+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}