{"resultsPerPage":1,"startIndex":0,"totalResults":1,"format":"NVD_CVE","version":"2.0","timestamp":"2026-05-05T18:26:43.962","vulnerabilities":[{"cve":{"id":"CVE-2024-49884","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","published":"2024-10-21T18:15:11.130","lastModified":"2025-11-03T23:16:28.680","vulnStatus":"Modified","cveTags":[],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\next4: fix slab-use-after-free in ext4_split_extent_at()\n\nWe hit the following use-after-free:\n\n==================================================================\nBUG: KASAN: slab-use-after-free in ext4_split_extent_at+0xba8/0xcc0\nRead of size 2 at addr ffff88810548ed08 by task kworker/u20:0/40\nCPU: 0 PID: 40 Comm: kworker/u20:0 Not tainted 6.9.0-dirty #724\nCall Trace:\n <TASK>\n kasan_report+0x93/0xc0\n ext4_split_extent_at+0xba8/0xcc0\n ext4_split_extent.isra.0+0x18f/0x500\n ext4_split_convert_extents+0x275/0x750\n ext4_ext_handle_unwritten_extents+0x73e/0x1580\n ext4_ext_map_blocks+0xe20/0x2dc0\n ext4_map_blocks+0x724/0x1700\n ext4_do_writepages+0x12d6/0x2a70\n[...]\n\nAllocated by task 40:\n __kmalloc_noprof+0x1ac/0x480\n ext4_find_extent+0xf3b/0x1e70\n ext4_ext_map_blocks+0x188/0x2dc0\n ext4_map_blocks+0x724/0x1700\n ext4_do_writepages+0x12d6/0x2a70\n[...]\n\nFreed by task 40:\n kfree+0xf1/0x2b0\n ext4_find_extent+0xa71/0x1e70\n ext4_ext_insert_extent+0xa22/0x3260\n ext4_split_extent_at+0x3ef/0xcc0\n ext4_split_extent.isra.0+0x18f/0x500\n ext4_split_convert_extents+0x275/0x750\n ext4_ext_handle_unwritten_extents+0x73e/0x1580\n ext4_ext_map_blocks+0xe20/0x2dc0\n ext4_map_blocks+0x724/0x1700\n ext4_do_writepages+0x12d6/0x2a70\n[...]\n==================================================================\n\nThe flow of issue triggering is as follows:\n\next4_split_extent_at\n  path = *ppath\n  ext4_ext_insert_extent(ppath)\n    ext4_ext_create_new_leaf(ppath)\n      ext4_find_extent(orig_path)\n        path = *orig_path\n        read_extent_tree_block\n          // return -ENOMEM or -EIO\n        ext4_free_ext_path(path)\n          kfree(path)\n        *orig_path = NULL\n  a. If err is -ENOMEM:\n  ext4_ext_dirty(path + path->p_depth)\n  // path use-after-free !!!\n  b. If err is -EIO and we have EXT_DEBUG defined:\n  ext4_ext_show_leaf(path)\n    eh = path[depth].p_hdr\n    // path also use-after-free !!!\n\nSo when trying to zeroout or fix the extent length, call ext4_find_extent()\nto update the path.\n\nIn addition we use *ppath directly as an ext4_ext_show_leaf() input to\navoid possible use-after-free when EXT_DEBUG is defined, and to avoid\nunnecessary path updates."},{"lang":"es","value":"En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: ext4: corrección de slab-use-after-free en ext4_split_extent_at() Nos topamos con el siguiente use after free: ====================================================================== ERROR: KASAN: slab-use-after-free en ext4_split_extent_at+0xba8/0xcc0 Lectura de tamaño 2 en la dirección ffff88810548ed08 por la tarea kworker/u20:0/40 CPU: 0 PID: 40 Comm: kworker/u20:0 No contaminado 6.9.0-dirty #724 Seguimiento de llamadas:  kasan_report+0x93/0xc0 ext4_split_extent_at+0xba8/0xcc0 ext4_split_extent.isra.0+0x18f/0x500 ext4_split_convert_extents+0x275/0x750 ext4_ext_handle_unwritten_extents+0x73e/0x1580 ext4_ext_map_blocks+0xe20/0x2dc0 ext4_map_blocks+0x724/0x1700 ext4_do_writepages+0x12d6/0x2a70 [...] Asignado por la tarea 40: __kmalloc_noprof+0x1ac/0x480 ext4_find_extent+0xf3b/0x1e70 ext4_ext_map_blocks+0x188/0x2dc0 ext4_map_blocks+0x724/0x1700 ext4_do_writepages+0x12d6/0x2a70 [...] Liberado por la tarea 40: kfree+0xf1/0x2b0 ext4_find_extent+0xa71/0x1e70 ext4_ext_insert_extent+0xa22/0x3260 ext4_split_extent_at+0x3ef/0xcc0 ext4_split_extent.isra.0+0x18f/0x500 ext4_split_convert_extents+0x275/0x750 ext4_ext_handle_unwritten_extents+0x73e/0x1580 ext4_ext_map_blocks+0xe20/0x2dc0 ext4_map_blocks+0x724/0x1700 ext4_do_writepages+0x12d6/0x2a70 [...] ==================================================================== El flujo de activación del problema es el siguiente: ext4_split_extent_at path = *ppath ext4_ext_insert_extent(ppath) ext4_ext_create_new_leaf(ppath) ext4_find_extent(orig_path) path = *orig_path read_extent_tree_block // devuelve -ENOMEM o -EIO ext4_free_ext_path(path) kfree(path) *orig_path = NULL a. Si err es -ENOMEM: ext4_ext_dirty(path + path-&gt;p_depth) // ¡¡¡path use after free!!! b. Si err es -EIO y tenemos EXT_DEBUG definido: ext4_ext_show_leaf(path) eh = path[depth].p_hdr // ¡¡¡La ruta también es use after free!!! Por lo tanto, cuando intente poner a cero o corregir la longitud de la extensión, llame a ext4_find_extent() para actualizar la ruta. Además, usamos *ppath directamente como una entrada de ext4_ext_show_leaf() para evitar un posible use after free cuando se define EXT_DEBUG y para evitar actualizaciones de ruta innecesarias."}],"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:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"},"exploitabilityScore":1.8,"impactScore":5.9}]},"weaknesses":[{"source":"nvd@nist.gov","type":"Primary","description":[{"lang":"en","value":"CWE-416"}]}],"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.18","versionEndExcluding":"5.10.227","matchCriteriaId":"5C882E98-F19D-47B6-A807-73BB9ABA763C"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.11","versionEndExcluding":"5.15.168","matchCriteriaId":"4D51C05D-455B-4D8D-89E7-A58E140B864C"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.16","versionEndExcluding":"6.1.113","matchCriteriaId":"D01BD22E-ACD1-4618-9D01-6116570BE1EE"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.2","versionEndExcluding":"6.6.55","matchCriteriaId":"E90B9576-56C4-47BC-AAB0-C5B2D438F5D0"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.7","versionEndExcluding":"6.10.14","matchCriteriaId":"4C16BCE0-FFA0-4599-BE0A-1FD65101C021"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11","versionEndExcluding":"6.11.3","matchCriteriaId":"54D9C704-D679-41A7-9C40-10A6B1E7FFE9"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/393a46f60ea4f249dc9d496d4eb2d542f5e11ade","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/448100a29395b0c8b4c42967155849fe0fbe808f","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/5d949ea75bb529ea6342e83465938a3b0ac51238","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/8fe117790b37c84c651e2bad9efc0e7fda73c0e3","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/915ac3630488af0ca194dc63b86d99802b4f6e18","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/a5401d4c3e2a3d25643c567d26e6de327774a2c9","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/c26ab35702f8cd0cdc78f96aa5856bfb77be798f","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/cafcc1bd62934547c76abf46c6d0d54f135006fe","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/e52f933598b781d291b9297e39c463536da0e185","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html","source":"af854a3a-2127-422b-91ae-364da2661108"}]}}]}