{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-63889", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-19T07:54:57.018Z", "datePublished": "2026-07-19T14:55:01.515Z", "dateUpdated": "2026-08-05T12:36:58.639Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:36:58.639Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nscsi: scsi_transport_fc: Widen FPIN pname walker counter to u32\n\nAn adjacent Fibre Channel fabric actor that can deliver an FPIN ELS\nframe to an lpfc or qla2xxx Linux initiator can trigger a non-return in\nthe generic FC transport. This is not a local userspace or IP network\npath; the attacker must be able to inject fabric traffic, for example as\na compromised switch or fabric controller, or as a same-zone N_Port on a\nfabric that permits source spoofing.\n\nThe Link-Integrity and Peer-Congestion FPIN walkers used a u8 loop\ncounter against the 32-bit on-wire pname_count field, and did not bound\npname_count by the descriptor body already validated by the TLV walker.\nA pname_count of 256 therefore wraps the counter and keeps the loop\ncondition true indefinitely.\n\nFactor the shared pname_list[] walk into one helper, widen the counter\nto u32, and clamp pname_count against the entries that fit in the\ndescriptor body before iterating." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H", "baseScore": 8.1, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:A - Exploitation requires injecting a crafted FPIN ELS frame onto the Fibre Channel fabric from an adjacent fabric actor (compromised switch, fabric controller, or same-zone N_Port), not via IP or local syscalls.\nAC:L - Once on the fabric, an attacker can reliably trigger the bug by sending an FPIN with a Link-Integrity or Peer-Congestion descriptor containing pname_count=256 and a minimally valid TLV length; no race or special memory layout is required.\nPR:N - The attacker needs no privileges on the victim Linux host; FPIN ELS frames are processed without authentication once the HBA has completed fabric discovery.\nUI:N - No victim user action is required; the malicious FPIN is processed automatically when received by the HBA firmware and driver stack.\nS:U - Impact is confined to kernel availability and information disclosure on the affected host; it does not cross a security boundary such as VM escape or sandbox breakout.\nC:H - The unbounded loop reads pname_list[i] beyond the validated descriptor body via out-of-bounds kernel memory reads on every iteration, enabling information disclosure from adjacent kernel memory.\nI:N - The bug causes only counter increments in FPIN statistics structures on matched rports; there is no memory corruption or write primitive that could modify arbitrary data or achieve code execution.\nA:H - The infinite loop pins a CPU in kernel context (potentially from interrupt/DPC paths) and repeatedly acquires host_lock via fc_find_rport_by_wwpn(), causing soft lockup and complete loss of host availability." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/scsi/scsi_transport_fc.c" ], "versions": [ { "version": "3dcfe0de5a9752e646a61f4ce513ac059960c7c3", "lessThan": "07776b7779c9426982c1ad74aad91bd531593790", "status": "affected", "versionType": "git" }, { "version": "3dcfe0de5a9752e646a61f4ce513ac059960c7c3", "lessThan": "29f126f09e34a425b376b3646c89aa7cc18b142c", "status": "affected", "versionType": "git" }, { "version": "3dcfe0de5a9752e646a61f4ce513ac059960c7c3", "lessThan": "163bd704d7515c3df6c2e03bcba93d1db79edbff", "status": "affected", "versionType": "git" }, { "version": "3dcfe0de5a9752e646a61f4ce513ac059960c7c3", "lessThan": "ee57b89e5da9fffbe0d26647e4ff0750dacb9943", "status": "affected", "versionType": "git" }, { "version": "3dcfe0de5a9752e646a61f4ce513ac059960c7c3", "lessThan": "35461d23744175a78b6280293892cca357c22793", "status": "affected", "versionType": "git" }, { "version": "3dcfe0de5a9752e646a61f4ce513ac059960c7c3", "lessThan": "bdff76dff6ec23d6fe35812fa33e5c4ce2cdb770", "status": "affected", "versionType": "git" }, { "version": "3dcfe0de5a9752e646a61f4ce513ac059960c7c3", "lessThan": "a9a39233ec1fc9f97ea1340a4d09bb7ec2be5153", "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/scsi/scsi_transport_fc.c" ], "versions": [ { "version": "5.11", "status": "affected" }, { "version": "0", "lessThan": "5.11", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.210", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.176", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.143", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.93", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.35", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.0.12", "lessThanOrEqual": "7.0.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1", "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": "5.11", "versionEndExcluding": "5.15.210" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.11", "versionEndExcluding": "6.1.176" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.11", "versionEndExcluding": "6.6.143" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.11", "versionEndExcluding": "6.12.93" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.11", "versionEndExcluding": "6.18.35" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.11", "versionEndExcluding": "7.0.12" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.11", "versionEndExcluding": "7.1" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/07776b7779c9426982c1ad74aad91bd531593790" }, { "url": "https://git.kernel.org/stable/c/29f126f09e34a425b376b3646c89aa7cc18b142c" }, { "url": "https://git.kernel.org/stable/c/163bd704d7515c3df6c2e03bcba93d1db79edbff" }, { "url": "https://git.kernel.org/stable/c/ee57b89e5da9fffbe0d26647e4ff0750dacb9943" }, { "url": "https://git.kernel.org/stable/c/35461d23744175a78b6280293892cca357c22793" }, { "url": "https://git.kernel.org/stable/c/bdff76dff6ec23d6fe35812fa33e5c4ce2cdb770" }, { "url": "https://git.kernel.org/stable/c/a9a39233ec1fc9f97ea1340a4d09bb7ec2be5153" } ], "title": "scsi: scsi_transport_fc: Widen FPIN pname walker counter to u32", "x_generator": { "engine": "bippy-1.2.0" } } } }