CVE-2026-23143

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-23143", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-01-13T15:37:45.973Z", "datePublished": "2026-02-14T15:36:08.834Z", "dateUpdated": "2026-10-21T12:38:54.971Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-21T12:38:54.971Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvirtio_net: Fix misalignment bug in struct virtnet_info\n\nUse the new TRAILING_OVERLAP() helper to fix a misalignment bug\nalong with the following warning:\n\ndrivers/net/virtio_net.c:429:46: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end]\n\nThis helper creates a union between a flexible-array member (FAM)\nand a set of members that would otherwise follow it (in this case\n`u8 rss_hash_key_data[VIRTIO_NET_RSS_MAX_KEY_SIZE];`). This\noverlays the trailing members (rss_hash_key_data) onto the FAM\n(hash_key_data) while keeping the FAM and the start of MEMBERS aligned.\nThe static_assert() ensures this alignment remains.\n\nNotice that due to tail padding in flexible `struct\nvirtio_net_rss_config_trailer`, `rss_trailer.hash_key_data`\n(at offset 83 in struct virtnet_info) and `rss_hash_key_data` (at\noffset 84 in struct virtnet_info) are misaligned by one byte. See\nbelow:\n\nstruct virtio_net_rss_config_trailer {\n __le16 max_tx_vq; /* 0 2 */\n __u8 hash_key_length; /* 2 1 */\n __u8 hash_key_data[]; /* 3 0 */\n\n /* size: 4, cachelines: 1, members: 3 */\n /* padding: 1 */\n /* last cacheline: 4 bytes */\n};\n\nstruct virtnet_info {\n...\n struct virtio_net_rss_config_trailer rss_trailer; /* 80 4 */\n\n /* XXX last struct has 1 byte of padding */\n\n u8 rss_hash_key_data[40]; /* 84 40 */\n...\n /* size: 832, cachelines: 13, members: 48 */\n /* sum members: 801, holes: 8, sum holes: 31 */\n /* paddings: 2, sum paddings: 5 */\n};\n\nAfter changes, those members are correctly aligned at offset 795:\n\nstruct virtnet_info {\n...\n union {\n struct virtio_net_rss_config_trailer rss_trailer; /* 792 4 */\n struct {\n unsigned char __offset_to_hash_key_data[3]; /* 792 3 */\n u8 rss_hash_key_data[40]; /* 795 40 */\n }; /* 792 43 */\n }; /* 792 44 */\n...\n /* size: 840, cachelines: 14, members: 47 */\n /* sum members: 801, holes: 8, sum holes: 35 */\n /* padding: 4 */\n /* paddings: 1, sum paddings: 4 */\n /* last cacheline: 8 bytes */\n};\n\nAs a result, the RSS key passed to the device is shifted by 1\nbyte: the last byte is cut off, and instead a (possibly\nuninitialized) byte is added at the beginning.\n\nAs a last note `struct virtio_net_rss_config_hdr *rss_hdr;` is also\nmoved to the end, since it seems those three members should stick\naround together. :)"}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/net/virtio_net.c"], "versions": [{"version": "4c47aff10f6f0a2506dc2126c17ccd4c42bfa211", "lessThan": "d1e9614a142eff34c93e94a15a71ad0e806799c4", "status": "affected", "versionType": "git"}, {"version": "ed3100e90d0d120a045a551b85eb43cf2527e885", "lessThan": "ae48108c2310f1dd700e0dbb655c2f1d92ed00fc", "status": "affected", "versionType": "git"}, {"version": "ed3100e90d0d120a045a551b85eb43cf2527e885", "lessThan": "4156c3745f06bc197094b9ee97a9584e69ed00bf", "status": "affected", "versionType": "git"}, {"version": "6.12.91", "lessThan": "6.12.114", "status": "affected", "versionType": "semver"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/net/virtio_net.c"], "versions": [{"version": "6.15", "status": "affected"}, {"version": "0", "lessThan": "6.15", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.114", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.7", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.19", "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": "6.12.91", "versionEndExcluding": "6.12.114"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.15", "versionEndExcluding": "6.18.7"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.15", "versionEndExcluding": "6.19"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/d1e9614a142eff34c93e94a15a71ad0e806799c4"}, {"url": "https://git.kernel.org/stable/c/ae48108c2310f1dd700e0dbb655c2f1d92ed00fc"}, {"url": "https://git.kernel.org/stable/c/4156c3745f06bc197094b9ee97a9584e69ed00bf"}], "title": "virtio_net: Fix misalignment bug in struct virtnet_info", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["drivers/net/virtio_net.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "d1e9614a142eff34c93e94a15a71ad0e806799c4", "status": "affected", "version": "4c47aff10f6f0a2506dc2126c17ccd4c42bfa211", "versionType": "git"}, {"lessThan": "ae48108c2310f1dd700e0dbb655c2f1d92ed00fc", "status": "affected", "version": "ed3100e90d0d120a045a551b85eb43cf2527e885", "versionType": "git"}, {"lessThan": "4156c3745f06bc197094b9ee97a9584e69ed00bf", "status": "affected", "version": "ed3100e90d0d120a045a551b85eb43cf2527e885", "versionType": "git"}, {"lessThan": "6.12.114", "status": "affected", "version": "6.12.91", "versionType": "semver"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["drivers/net/virtio_net.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "6.15"}, {"lessThan": "6.15", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.114", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.7", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "6.19", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "2446B98C-005E-4681-A566-03D3F408B450", "versionEndExcluding": "6.18.7", "versionStartIncluding": "6.15", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc1:*:*:*:*:*:*", "matchCriteriaId": "17B67AA7-40D6-4AFA-8459-F200F3D7CFD1", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc2:*:*:*:*:*:*", "matchCriteriaId": "C47E4CC9-C826-4FA9-B014-7FE3D9B318B2", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc3:*:*:*:*:*:*", "matchCriteriaId": "F71D92C0-C023-48BD-B3B6-70B638EEE298", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc4:*:*:*:*:*:*", "matchCriteriaId": "13580667-0A98-40CC-B29F-D12790B91BDB", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc5:*:*:*:*:*:*", "matchCriteriaId": "CAD1FED7-CF48-47BF-AC7D-7B6FA3C065FC", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvirtio_net: Fix misalignment bug in struct virtnet_info\n\nUse the new TRAILING_OVERLAP() helper to fix a misalignment bug\nalong with the following warning:\n\ndrivers/net/virtio_net.c:429:46: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end]\n\nThis helper creates a union between a flexible-array member (FAM)\nand a set of members that would otherwise follow it (in this case\n`u8 rss_hash_key_data[VIRTIO_NET_RSS_MAX_KEY_SIZE];`). This\noverlays the trailing members (rss_hash_key_data) onto the FAM\n(hash_key_data) while keeping the FAM and the start of MEMBERS aligned.\nThe static_assert() ensures this alignment remains.\n\nNotice that due to tail padding in flexible `struct\nvirtio_net_rss_config_trailer`, `rss_trailer.hash_key_data`\n(at offset 83 in struct virtnet_info) and `rss_hash_key_data` (at\noffset 84 in struct virtnet_info) are misaligned by one byte. See\nbelow:\n\nstruct virtio_net_rss_config_trailer {\n __le16 max_tx_vq; /* 0 2 */\n __u8 hash_key_length; /* 2 1 */\n __u8 hash_key_data[]; /* 3 0 */\n\n /* size: 4, cachelines: 1, members: 3 */\n /* padding: 1 */\n /* last cacheline: 4 bytes */\n};\n\nstruct virtnet_info {\n...\n struct virtio_net_rss_config_trailer rss_trailer; /* 80 4 */\n\n /* XXX last struct has 1 byte of padding */\n\n u8 rss_hash_key_data[40]; /* 84 40 */\n...\n /* size: 832, cachelines: 13, members: 48 */\n /* sum members: 801, holes: 8, sum holes: 31 */\n /* paddings: 2, sum paddings: 5 */\n};\n\nAfter changes, those members are correctly aligned at offset 795:\n\nstruct virtnet_info {\n...\n union {\n struct virtio_net_rss_config_trailer rss_trailer; /* 792 4 */\n struct {\n unsigned char __offset_to_hash_key_data[3]; /* 792 3 */\n u8 rss_hash_key_data[40]; /* 795 40 */\n }; /* 792 43 */\n }; /* 792 44 */\n...\n /* size: 840, cachelines: 14, members: 47 */\n /* sum members: 801, holes: 8, sum holes: 35 */\n /* padding: 4 */\n /* paddings: 1, sum paddings: 4 */\n /* last cacheline: 8 bytes */\n};\n\nAs a result, the RSS key passed to the device is shifted by 1\nbyte: the last byte is cut off, and instead a (possibly\nuninitialized) byte is added at the beginning.\n\nAs a last note `struct virtio_net_rss_config_hdr *rss_hdr;` is also\nmoved to the end, since it seems those three members should stick\naround together. :)"}, {"lang": "es", "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nvirtio_net: Corrige un error de desalineaci\u00f3n en la estructura virtnet_info\n\nUsa el nuevo ayudante TRAILING_OVERLAP() para corregir un error de desalineaci\u00f3n junto con la siguiente advertencia:\n\ndrivers/net/virtio_net.c:429:46: advertencia: la estructura que contiene un miembro de array flexible no est\u00e1 al final de otra estructura [-Wflex-array-member-not-at-end]\n\nEste ayudante crea una uni\u00f3n entre un miembro de array flexible (FAM) y un conjunto de miembros que de otro modo lo seguir\u00edan (en este caso 'u8 rss_hash_key_data[VIRTIO_NET_RSS_MAX_KEY_SIZE];'). Esto superpone los miembros finales (rss_hash_key_data) sobre el FAM (hash_key_data) mientras mantiene el FAM y el inicio de los MIEMBROS alineados. El static_assert() asegura que esta alineaci\u00f3n se mantenga.\n\nN\u00f3tese que debido al relleno de cola en la estructura flexible 'struct virtio_net_rss_config_trailer', 'rss_trailer.hash_key_data' (en el desplazamiento 83 en la estructura virtnet_info) y 'rss_hash_key_data' (en el desplazamiento 84 en la estructura virtnet_info) est\u00e1n desalineados por un byte. Ver a continuaci\u00f3n:\n\n```\nstruct virtio_net_rss_config_trailer {\n __le16 max_tx_vq; /* 0 2 */\n __u8 hash_key_length; /* 2 1 */\n __u8 hash_key_data[]; /* 3 0 */\n\n /* size: 4, cachelines: 1, members: 3 */\n /* padding: 1 */\n /* last cacheline: 4 bytes */\n};\n```\n\n```\nstruct virtnet_info {\n...\n struct virtio_net_rss_config_trailer rss_trailer; /* 80 4 */\n\n /* XXX last struct has 1 byte of padding */\n\n u8 rss_hash_key_data[40]; /* 84 40 */\n...\n /* size: 832, cachelines: 13, members: 48 */\n /* sum members: 801, holes: 8, sum holes: 31 */\n /* paddings: 2, sum paddings: 5 */\n};\n```\n\nDespu\u00e9s de los cambios, esos miembros est\u00e1n correctamente alineados en el desplazamiento 795:\n\n```\nstruct virtnet_info {\n...\n union {\n struct virtio_net_rss_config_trailer rss_trailer; /* 792 4 */\n struct {\n unsigned char __offset_to_hash_key_data[3]; /* 792 3 */\n u8 rss_hash_key_data[40]; /* 795 40 */\n }; /* 792 43 */\n }; /* 792 44 */\n...\n /* size: 840, cachelines: 14, members: 47 */\n /* sum members: 801, holes: 8, sum holes: 35 */\n /* padding: 4 */\n /* paddings: 1, sum paddings: 4 */\n /* last cacheline: 8 bytes */\n};\n```\n\nComo resultado, la clave RSS pasada al dispositivo se desplaza 1 byte: el \u00faltimo byte se corta y, en su lugar, se a\u00f1ade un byte (posiblemente no inicializado) al principio.\n\nComo \u00faltima nota, 'struct virtio_net_rss_config_hdr *rss_hdr;' tambi\u00e9n se mueve al final, ya que parece que esos tres miembros deber\u00edan permanecer juntos. :)"}], "id": "CVE-2026-23143", "lastModified": "2026-10-21T13:18:33.787", "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": "2026-02-14T16:15:54.383", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/4156c3745f06bc197094b9ee97a9584e69ed00bf"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/ae48108c2310f1dd700e0dbb655c2f1d92ed00fc"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/d1e9614a142eff34c93e94a15a71ad0e806799c4"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "NVD-CWE-noinfo"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"bugzilla": {"description": "kernel: virtio_net: Fix misalignment bug in struct virtnet_info", "id": "2439851", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2439851"}, "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"}, "details": ["No description is available for this CVE."], "name": "CVE-2026-23143", "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": "2026-02-14T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-23143\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-23143\nhttps://lore.kernel.org/linux-cve-announce/2026021416-CVE-2026-23143-9346@gregkh/T"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[ed3100e90d0d120a045a551b85eb43cf2527e885,ae48108c2310f1dd700e0dbb655c2f1d92ed00fc)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[ed3100e90d0d120a045a551b85eb43cf2527e885,4156c3745f06bc197094b9ee97a9584e69ed00bf)"}}], "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "6.15"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,6.15)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.7,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.19,*]"}}], "product": "linux_kernel", "vendor": "linux"}], "analysis": {"en": {"generated_at": "2026-04-18T20:36:49.410452+00:00", "value": {"mitigation_remediation": ["Update the Linux kernel to a version that includes the commit fixing the misalignment bug (for example, kernel 6.19 rc5 or a later release).", "If a kernel upgrade cannot be performed immediately, disable RSS configuration on virtio devices or configure them to use RSS keys that avoid the misaligned region.", "Monitor the system for abnormal network performance or packet routing anomalies that could indicate use of a misaligned RSS key."], "summary": {"action": "Patch Kernel", "impact": "Data Integrity / Network Misconfiguration"}, "threat_synthesis": {"affected_systems": "Linux kernel builds before the commit introducing the TRAILING_OVERLAP helper are affected. This includes the 6.19 release candidates rc1 through rc5 and any downstream releases based on those revisions that have not incorporated the fix. Distributions shipping these kernels without the patch remain vulnerable.", "description_and_impact": "A bug in the Linux kernel\u2019s virtio_net driver caused a misalignment between a flexible\u2011array member and a following fixed\u2011size array inside the struct virtnet_info. This misplacement shifted the RSS hash key sent to the virtio device by one byte, resulting in a truncated final byte and an uninitialized leading byte. The altered key can lead to incorrect packet hashes, which may mis\u2011route traffic or degrade network performance, but does not grant code execution or other privilege escalations.", "risk_and_exploitability": "The CVSS score of 5.5 rates the vulnerability as medium impact. The EPSS score is below 1\u202f% and it is not listed in CISA KEV, indicating a low likelihood of widespread exploitation. Exploitation would require local or privileged access to reconfigure RSS settings on a virtio device and does not provide remote code execution. Overall risk is moderate and best practice is to apply the kernel patch as soon as feasible."}}}}, "created": "2026-02-16T12:01:23.574920+00:00", "updated": "2026-04-18T20:45:05.719880+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}