{"resultsPerPage":1,"startIndex":0,"totalResults":1,"format":"NVD_CVE","version":"2.0","timestamp":"2026-05-05T11:13:17.756","vulnerabilities":[{"cve":{"id":"CVE-2026-23143","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","published":"2026-02-14T16:15:54.383","lastModified":"2026-03-17T21:13:32.820","vulnStatus":"Analyzed","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 desalineación en la estructura virtnet_info\n\nUsa el nuevo ayudante TRAILING_OVERLAP() para corregir un error de desalineación junto con la siguiente advertencia:\n\ndrivers/net/virtio_net.c:429:46: advertencia: la estructura que contiene un miembro de array flexible no está al final de otra estructura [-Wflex-array-member-not-at-end]\n\nEste ayudante crea una unión entre un miembro de array flexible (FAM) y un conjunto de miembros que de otro modo lo seguirían (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 alineación se mantenga.\n\nNótese 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) están desalineados por un byte. Ver a continuación:\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\nDespués de los cambios, esos miembros están 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 último byte se corta y, en su lugar, se añade un byte (posiblemente no inicializado) al principio.\n\nComo última nota, 'struct virtio_net_rss_config_hdr *rss_hdr;' también se mueve al final, ya que parece que esos tres miembros deberían permanecer juntos. :)"}],"metrics":{"cvssMetricV31":[{"source":"nvd@nist.gov","type":"Primary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","baseScore":5.5,"baseSeverity":"MEDIUM","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":1.8,"impactScore":3.6}]},"weaknesses":[{"source":"nvd@nist.gov","type":"Primary","description":[{"lang":"en","value":"NVD-CWE-noinfo"}]}],"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.15","versionEndExcluding":"6.18.7","matchCriteriaId":"2446B98C-005E-4681-A566-03D3F408B450"},{"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"}]}]}],"references":[{"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","tags":["Patch"]}]}}]}