CVE-2026-23355

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-23355", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-01-13T15:37:46.000Z", "datePublished": "2026-03-25T10:27:39.514Z", "dateUpdated": "2026-10-30T12:23:58.074Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-30T12:23:58.074Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nata: libata: cancel pending work after clearing deferred_qc\n\nSyzbot reported a WARN_ON() in ata_scsi_deferred_qc_work(), caused by\nap->ops->qc_defer() returning non-zero before issuing the deferred qc.\n\nata_scsi_schedule_deferred_qc() is called during each command completion.\nThis function will check if there is a deferred QC, and if\nap->ops->qc_defer() returns zero, meaning that it is possible to queue the\ndeferred qc at this time (without being deferred), then it will queue the\nwork which will issue the deferred qc.\n\nOnce the work get to run, which can potentially be a very long time after\nthe work was scheduled, there is a WARN_ON() if ap->ops->qc_defer() returns\nnon-zero.\n\nWhile we hold the ap->lock both when assigning and clearing deferred_qc,\nand the work itself holds the ap->lock, the code currently does not cancel\nthe work after clearing the deferred qc.\n\nThis means that the following scenario can happen:\n1) One or several NCQ commands are queued.\n2) A non-NCQ command is queued, gets stored in ap->deferred_qc.\n3) Last NCQ command gets completed, work is queued to issue the deferred\n qc.\n4) Timeout or error happens, ap->deferred_qc is cleared. The queued work is\n currently NOT canceled.\n5) Port is reset.\n6) One or several NCQ commands are queued.\n7) A non-NCQ command is queued, gets stored in ap->deferred_qc.\n8) Work is finally run. Yet at this time, there is still NCQ commands in\n flight.\n\nThe work in 8) really belongs to the non-NCQ command in 2), not to the\nnon-NCQ command in 7). The reason why the work is executed when it is not\nsupposed to, is because it was never canceled when ap->deferred_qc was\ncleared in 4). Thus, ensure that we always cancel the work after clearing\nap->deferred_qc.\n\nAnother potential fix would have been to let ata_scsi_deferred_qc_work() do\nnothing if ap->ops->qc_defer() returns non-zero. However, canceling the\nwork when clearing ap->deferred_qc seems slightly more logical, as we hold\nthe ap->lock when clearing ap->deferred_qc, so we know that the work cannot\nbe holding the lock. (The function could be waiting for the lock, but that\nis okay since it will do nothing if ap->deferred_qc is not set.)"}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/ata/libata-eh.c", "drivers/ata/libata-scsi.c"], "versions": [{"version": "ce22aaed011206fed9cbd8c9c2d44718607f31ee", "lessThan": "0d12453818c35e1ded84633152c6b05002ae48b9", "status": "affected", "versionType": "git"}, {"version": "888cd7e40adb2ef4af1b4d3b6e2e83ad409ae8c2", "lessThan": "6c5e8f16b5e8e614e829aaf38619bdd79107bb0a", "status": "affected", "versionType": "git"}, {"version": "5d61a38a60e62750526d94663b69b7ac5c7f07a5", "lessThan": "58e658763ba2aa9168d8516b98a6314d7461a53e", "status": "affected", "versionType": "git"}, {"version": "0ea84089dbf62a92dc7889c79e6b18fc89260808", "lessThan": "aac9b27f7c1f2b2cf7f50a9ca633ecbbcaf22af9", "status": "affected", "versionType": "git"}, {"version": "c475bfce918dc413c4d59b97710b94b1c955ea5f", "status": "affected", "versionType": "git"}, {"version": "33abac5b5a5303ba2c66d89e063a806033be07fc", "status": "affected", "versionType": "git"}, {"version": "21e0d7a15a789e99be89231dae25cb6ffc482a7c", "status": "affected", "versionType": "git"}, {"version": "6.1.191", "lessThan": "6.2", "status": "affected", "versionType": "semver"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/ata/libata-eh.c", "drivers/ata/libata-scsi.c"], "versions": [{"version": "6.18.14", "lessThan": "6.18.18", "status": "affected", "versionType": "semver"}, {"version": "6.19.4", "lessThan": "6.19.7", "status": "affected", "versionType": "semver"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.18.14", "versionEndExcluding": "6.18.18"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19.4", "versionEndExcluding": "6.19.7"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1.191"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/0d12453818c35e1ded84633152c6b05002ae48b9"}, {"url": "https://git.kernel.org/stable/c/6c5e8f16b5e8e614e829aaf38619bdd79107bb0a"}, {"url": "https://git.kernel.org/stable/c/58e658763ba2aa9168d8516b98a6314d7461a53e"}, {"url": "https://git.kernel.org/stable/c/aac9b27f7c1f2b2cf7f50a9ca633ecbbcaf22af9"}], "title": "ata: libata: cancel pending work after clearing deferred_qc", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["drivers/ata/libata-eh.c", "drivers/ata/libata-scsi.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "0d12453818c35e1ded84633152c6b05002ae48b9", "status": "affected", "version": "ce22aaed011206fed9cbd8c9c2d44718607f31ee", "versionType": "git"}, {"lessThan": "6c5e8f16b5e8e614e829aaf38619bdd79107bb0a", "status": "affected", "version": "888cd7e40adb2ef4af1b4d3b6e2e83ad409ae8c2", "versionType": "git"}, {"lessThan": "58e658763ba2aa9168d8516b98a6314d7461a53e", "status": "affected", "version": "5d61a38a60e62750526d94663b69b7ac5c7f07a5", "versionType": "git"}, {"lessThan": "aac9b27f7c1f2b2cf7f50a9ca633ecbbcaf22af9", "status": "affected", "version": "0ea84089dbf62a92dc7889c79e6b18fc89260808", "versionType": "git"}, {"status": "affected", "version": "c475bfce918dc413c4d59b97710b94b1c955ea5f", "versionType": "git"}, {"status": "affected", "version": "33abac5b5a5303ba2c66d89e063a806033be07fc", "versionType": "git"}, {"status": "affected", "version": "21e0d7a15a789e99be89231dae25cb6ffc482a7c", "versionType": "git"}, {"lessThan": "6.2", "status": "affected", "version": "6.1.191", "versionType": "semver"}]}, {"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["drivers/ata/libata-eh.c", "drivers/ata/libata-scsi.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "6.18.18", "status": "affected", "version": "6.18.14", "versionType": "semver"}, {"lessThan": "6.19.7", "status": "affected", "version": "6.19.4", "versionType": "semver"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "670AAACD-4EEC-4150-9192-29029F51935B", "versionEndExcluding": "6.18.18", "versionStartIncluding": "6.18.14", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "EABFC675-2A5E-4569-92F7-1E8942DA0683", "versionEndExcluding": "6.19.7", "versionStartIncluding": "6.19.4", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*", "matchCriteriaId": "F253B622-8837-4245-BCE5-A7BF8FC76A16", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*", "matchCriteriaId": "4AE85AD8-4641-4E7C-A2F4-305E2CD9EE64", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nata: libata: cancel pending work after clearing deferred_qc\n\nSyzbot reported a WARN_ON() in ata_scsi_deferred_qc_work(), caused by\nap->ops->qc_defer() returning non-zero before issuing the deferred qc.\n\nata_scsi_schedule_deferred_qc() is called during each command completion.\nThis function will check if there is a deferred QC, and if\nap->ops->qc_defer() returns zero, meaning that it is possible to queue the\ndeferred qc at this time (without being deferred), then it will queue the\nwork which will issue the deferred qc.\n\nOnce the work get to run, which can potentially be a very long time after\nthe work was scheduled, there is a WARN_ON() if ap->ops->qc_defer() returns\nnon-zero.\n\nWhile we hold the ap->lock both when assigning and clearing deferred_qc,\nand the work itself holds the ap->lock, the code currently does not cancel\nthe work after clearing the deferred qc.\n\nThis means that the following scenario can happen:\n1) One or several NCQ commands are queued.\n2) A non-NCQ command is queued, gets stored in ap->deferred_qc.\n3) Last NCQ command gets completed, work is queued to issue the deferred\n qc.\n4) Timeout or error happens, ap->deferred_qc is cleared. The queued work is\n currently NOT canceled.\n5) Port is reset.\n6) One or several NCQ commands are queued.\n7) A non-NCQ command is queued, gets stored in ap->deferred_qc.\n8) Work is finally run. Yet at this time, there is still NCQ commands in\n flight.\n\nThe work in 8) really belongs to the non-NCQ command in 2), not to the\nnon-NCQ command in 7). The reason why the work is executed when it is not\nsupposed to, is because it was never canceled when ap->deferred_qc was\ncleared in 4). Thus, ensure that we always cancel the work after clearing\nap->deferred_qc.\n\nAnother potential fix would have been to let ata_scsi_deferred_qc_work() do\nnothing if ap->ops->qc_defer() returns non-zero. However, canceling the\nwork when clearing ap->deferred_qc seems slightly more logical, as we hold\nthe ap->lock when clearing ap->deferred_qc, so we know that the work cannot\nbe holding the lock. (The function could be waiting for the lock, but that\nis okay since it will do nothing if ap->deferred_qc is not set.)"}, {"lang": "es", "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nata: libata: cancelar trabajo pendiente despu\u00e9s de limpiar deferred_qc\n\nSyzbot inform\u00f3 un WARN_ON() en ata_scsi_deferred_qc_work(), causado por ap->ops->qc_defer() que devolv\u00eda un valor distinto de cero antes de emitir el qc diferido.\n\nata_scsi_schedule_deferred_qc() es llamada durante cada finalizaci\u00f3n de comando. Esta funci\u00f3n verificar\u00e1 si hay un QC diferido, y si ap->ops->qc_defer() devuelve cero, lo que significa que es posible encolar el qc diferido en este momento (sin ser diferido), entonces encolar\u00e1 el trabajo que emitir\u00e1 el qc diferido.\n\nUna vez que el trabajo se ejecuta, lo que potencialmente puede ser mucho tiempo despu\u00e9s de que el trabajo fue programado, hay un WARN_ON() si ap->ops->qc_defer() devuelve un valor distinto de cero.\n\nMientras mantenemos el ap->lock tanto al asignar como al limpiar deferred_qc, y el trabajo en s\u00ed mantiene el ap->lock, el c\u00f3digo actualmente no cancela el trabajo despu\u00e9s de limpiar el qc diferido.\n\nEsto significa que el siguiente escenario puede ocurrir:\n1) Uno o varios comandos NCQ son encolados.\n2) Un comando no-NCQ es encolado, se almacena en ap->deferred_qc.\n3) El \u00faltimo comando NCQ se completa, el trabajo es encolado para emitir el qc diferido.\n4) Ocurre un tiempo de espera o un error, ap->deferred_qc es limpiado. El trabajo encolado NO es cancelado actualmente.\n5) El puerto es reiniciado.\n6) Uno o varios comandos NCQ son encolados.\n7) Un comando no-NCQ es encolado, se almacena en ap->deferred_qc.\n8) El trabajo finalmente se ejecuta. Sin embargo, en este momento, todav\u00eda hay comandos NCQ en curso.\n\nEl trabajo en 8) realmente pertenece al comando no-NCQ en 2), no al comando no-NCQ en 7). La raz\u00f3n por la cual el trabajo se ejecuta cuando no se supone que debe hacerlo, es porque nunca fue cancelado cuando ap->deferred_qc fue limpiado en 4). Por lo tanto, aseg\u00farese de que siempre cancelemos el trabajo despu\u00e9s de limpiar ap->deferred_qc.\n\nOtra soluci\u00f3n potencial habr\u00eda sido dejar que ata_scsi_deferred_qc_work() no hiciera nada si ap->ops->qc_defer() devuelve un valor distinto de cero. Sin embargo, cancelar el trabajo al limpiar ap->deferred_qc parece ligeramente m\u00e1s l\u00f3gico, ya que mantenemos el ap->lock al limpiar ap->deferred_qc, por lo que sabemos que el trabajo no puede estar manteniendo el bloqueo. (La funci\u00f3n podr\u00eda estar esperando el bloqueo, pero eso est\u00e1 bien ya que no har\u00e1 nada si ap->deferred_qc no est\u00e1 configurado.)"}], "id": "CVE-2026-23355", "lastModified": "2026-10-30T13:18:36.997", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 5.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 3.6, "source": "nvd@nist.gov", "type": "Primary"}]}, "published": "2026-03-25T11:16:34.110", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/0d12453818c35e1ded84633152c6b05002ae48b9"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/58e658763ba2aa9168d8516b98a6314d7461a53e"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/6c5e8f16b5e8e614e829aaf38619bdd79107bb0a"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/aac9b27f7c1f2b2cf7f50a9ca633ecbbcaf22af9"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "NVD-CWE-noinfo"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"bugzilla": {"description": "kernel: ata: libata: cancel pending work after clearing deferred_qc", "id": "2451249", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2451249"}, "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-459", "details": ["A flaw was found in the Linux kernel's libata subsystem. This vulnerability occurs due to improper handling of deferred work. When ap->deferred_qc is cleared, the associated queued work is not canceled, leading to the work being executed at an inappropriate time. This can result in a WARN_ON() condition, potentially causing system instability or a denial of service."], "name": "CVE-2026-23355", "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": "Out of support scope", "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": "2026-03-25T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-23355\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-23355\nhttps://lore.kernel.org/linux-cve-announce/2026032537-CVE-2026-23355-86df@gregkh/T"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[ce22aaed011206fed9cbd8c9c2d44718607f31ee,0d12453818c35e1ded84633152c6b05002ae48b9)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[888cd7e40adb2ef4af1b4d3b6e2e83ad409ae8c2,6c5e8f16b5e8e614e829aaf38619bdd79107bb0a)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[5d61a38a60e62750526d94663b69b7ac5c7f07a5,58e658763ba2aa9168d8516b98a6314d7461a53e)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[0ea84089dbf62a92dc7889c79e6b18fc89260808,aac9b27f7c1f2b2cf7f50a9ca633ecbbcaf22af9)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "33abac5b5a5303ba2c66d89e063a806033be07fc"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "21e0d7a15a789e99be89231dae25cb6ffc482a7c"}}], "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": "semver", "value": "7.0-rc1"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[0,7.0-rc1)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.18,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.19.7,6.20.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.0-rc3,*]"}}], "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"}], "analysis": {"en": {"generated_at": "2026-04-28T22:01:35.795008+00:00", "value": {"mitigation_remediation": ["Apply the Linux kernel patch that corrects libata deferred QC cancellation logic", "If an immediate patch is unavailable, avoid using non\u2011NCQ commands or temporarily disable NCQ on affected storage devices to prevent the deferred QC path from being triggered", "Monitor kernel logs (e.g., dmesg) for WARN_ON messages related to qc_defer failures and apply the patch promptly when such logs appear"], "summary": {"action": "Patch It", "impact": "Device instability and potential local disruption"}, "threat_synthesis": {"affected_systems": "All Linux kernel builds released before the patch that introduces the cancellation logic for deferred QC are affected, regardless of distribution or hardware configuration. The vulnerability exists in the kernel itself, so any system running an unpatched kernel version is at risk.", "description_and_impact": "In the Linux kernel, a flaw in libata prevents pending work associated with a deferred queue command (QC) from being cancelled once the deferred QC is cleared. When the stray work later runs, it may attempt to execute a command that no longer belongs to the original request, causing WARN_ON messages and possible device resets. The weak area is a lack of proper cancellation logic, leading to incorrect command handling and instability. This is a local issue rooted in improper resource cleanup.", "risk_and_exploitability": "The CVSS score of 5.5 indicates a moderate severity. The EPSS score of less than 1% suggests a very low probability of exploitation in the wild. The vulnerability is not listed in CISA\u2019s KEV catalog. Based on the description, it is inferred that exploitation would likely require a local user or a user with elevated privileges that can issue SATA commands triggering the deferred QC logic. Therefore, the risk is largely limited to local impact rather than remote exploitation."}}}}, "created": "2026-03-25T21:32:00.382133+00:00", "updated": "2026-04-28T22:15:41.357911+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}