{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2024-44992", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-08-21T05:34:56.671Z", "datePublished": "2024-09-04T19:54:38.878Z", "dateUpdated": "2026-08-05T11:37:32.018Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T11:37:32.018Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb/client: avoid possible NULL dereference in cifs_free_subrequest()\n\nClang static checker (scan-build) warning:\n\tcifsglob.h:line 890, column 3\n\tAccess to field 'ops' results in a dereference of a null pointer.\n\nCommit 519be989717c (\"cifs: Add a tracepoint to track credits involved in\nR/W requests\") adds a check for 'rdata->server', and let clang throw this\nwarning about NULL dereference.\n\nWhen 'rdata->credits.value != 0 && rdata->server == NULL' happens,\nadd_credits_and_wake_if() will call rdata->server->ops->add_credits().\nThis will cause NULL dereference problem. Add a check for 'rdata->server'\nto avoid NULL dereference." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "baseScore": 7.5, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:N - The precondition for the crash — `rdata->server` being NULL while credits are still held — is produced by SMB channel teardown paths (`cifs_chan_skip_or_disable()`, channel reconnect/disable) that are driven by the remote SMB server's responses and multichannel advertisements, so a malicious, compromised, or MITM'd SMB server reached over the network controls the trigger against a mounted client.\nAC:L - A hostile server controls both sides: it drives the reconnect/multichannel-disable that NULLs the channel and it controls response timing, so it can stall in-flight R/W subrequests to hold credits across the window at will. No memory-layout or victim-state condition outside the attacker's influence is needed.\nPR:N - A remote SMB server needs no account, credentials, or privileges on the victim client — the reconnect and channel-negotiation behaviour it abuses is part of normal connection maintenance on an established mount.\nUI:N - Against the common deployment of a persistent SMB mount (fstab/automount on servers, embedded and Android devices), the attacker acts on an already-mounted share with ordinary background readahead and writeback supplying the I/O; no victim action is required at attack time.\nS:U - The fault occurs in the CIFS client inside the kernel and its consequences stay within that same kernel's security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:N - The defect is a dereference of a NULL `server` pointer to reach `server->ops`, which faults immediately; no out-of-bounds or freed memory is read and no data is returned to the attacker.\nI:N - Nothing is written through the bad pointer — the code path faults on the read of `->ops` before any store, giving no write primitive or control-flow hijack on configurations with the standard non-zero `mmap_min_addr` and SMAP/PAN.\nA:H - The NULL dereference oopses the kernel in netfs subrequest-completion context, which is frequently a workqueue, killing writeback and rendering the mount unusable; the remote server can trigger it repeatedly." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/smb/client/file.c" ], "versions": [ { "version": "69c3c023af25edb5433a2db824d3e7cc328f0183", "lessThan": "fead60a6d5f84b472b928502a42c419253afe6c1", "status": "affected", "versionType": "git" }, { "version": "69c3c023af25edb5433a2db824d3e7cc328f0183", "lessThan": "74c2ab6d653b4c2354df65a7f7f2df1925a40a51", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/smb/client/file.c" ], "versions": [ { "version": "6.10", "status": "affected" }, { "version": "0", "lessThan": "6.10", "status": "unaffected", "versionType": "semver" }, { "version": "6.10.7", "lessThanOrEqual": "6.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.11", "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": "6.10", "versionEndExcluding": "6.10.7" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.10", "versionEndExcluding": "6.11" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/fead60a6d5f84b472b928502a42c419253afe6c1" }, { "url": "https://git.kernel.org/stable/c/74c2ab6d653b4c2354df65a7f7f2df1925a40a51" } ], "title": "smb/client: avoid possible NULL dereference in cifs_free_subrequest()", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "timestamp": "2024-09-04T20:19:34.019685Z", "id": "CVE-2024-44992", "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": "2024-09-04T20:19:53.480Z" } } ] } }