{"resultsPerPage":1,"startIndex":0,"totalResults":1,"format":"NVD_CVE","version":"2.0","timestamp":"2026-04-21T04:07:06.265","vulnerabilities":[{"cve":{"id":"CVE-2021-47221","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","published":"2024-05-21T15:15:11.380","lastModified":"2025-04-29T19:07:02.250","vulnStatus":"Analyzed","cveTags":[],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nmm/slub: actually fix freelist pointer vs redzoning\n\nIt turns out that SLUB redzoning (\"slub_debug=Z\") checks from\ns->object_size rather than from s->inuse (which is normally bumped to\nmake room for the freelist pointer), so a cache created with an object\nsize less than 24 would have the freelist pointer written beyond\ns->object_size, causing the redzone to be corrupted by the freelist\npointer.  This was very visible with \"slub_debug=ZF\":\n\n  BUG test (Tainted: G    B            ): Right Redzone overwritten\n  -----------------------------------------------------------------------------\n\n  INFO: 0xffff957ead1c05de-0xffff957ead1c05df @offset=1502. First byte 0x1a instead of 0xbb\n  INFO: Slab 0xffffef3950b47000 objects=170 used=170 fp=0x0000000000000000 flags=0x8000000000000200\n  INFO: Object 0xffff957ead1c05d8 @offset=1496 fp=0xffff957ead1c0620\n\n  Redzone  (____ptrval____): bb bb bb bb bb bb bb bb               ........\n  Object   (____ptrval____): 00 00 00 00 00 f6 f4 a5               ........\n  Redzone  (____ptrval____): 40 1d e8 1a aa                        @....\n  Padding  (____ptrval____): 00 00 00 00 00 00 00 00               ........\n\nAdjust the offset to stay within s->object_size.\n\n(Note that no caches of in this size range are known to exist in the\nkernel currently.)"},{"lang":"es","value":"En el kernel de Linux, se resolvió la siguiente vulnerabilidad: mm/slub: en realidad corrige el puntero de lista libre frente a redzoning. Resulta que SLUB redzoning (\"slub_debug=Z\") verifica desde s-&gt;object_size en lugar de s-&gt;inuse (que normalmente se elimina para dejar espacio para el puntero de lista libre), por lo que un caché creado con un tamaño de objeto menor a 24 tendría el puntero de lista libre escrito más allá de s-&gt;object_size, causando que el puntero de lista libre corrompa la zona roja. Esto fue muy visible con \"slub_debug=ZF\": prueba de BUG(contaminada: GB): zona roja derecha sobrescrita ---------------------------- ------------------------------------------------- INFORMACIÓN : 0xffff957ead1c05de-0xffff957ead1c05df @offset=1502. Primer byte 0x1a en lugar de 0xbb INFORMACIÓN: slab 0xffffef3950b47000 objetos=170 usados=170 fp=0x0000000000000000 banderas=0x80000000000000200 INFORMACIÓN: Objeto 0xffff957ead1c05d8 @offset=1496 fp=0xffff9 57ead1c0620 Zona roja (____ptrval____): bb bb bb bb bb bb bb bb .... .... Objeto (____ptrval____): 00 00 00 00 00 f6 f4 a5 ........ Redzone (____ptrval____): 40 1d e8 1a aa @.... Relleno (____ptrval____): 00 00 00 00 00 00 00 00 ........ Ajuste el desplazamiento para permanecer dentro de s-&gt;object_size. (Tenga en cuenta que actualmente no se sabe que existan cachés de este rango de tamaño en el kernel)."}],"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":"CWE-763"}]}],"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"5.10.46","matchCriteriaId":"366D4F8F-9C74-4363-B945-AE477F73A08A"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.11","versionEndExcluding":"5.12.13","matchCriteriaId":"7806E7E5-6D4F-4E18-81C1-79B3C60EE855"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:5.13:rc1:*:*:*:*:*:*","matchCriteriaId":"0CBAD0FC-C281-4666-AB2F-F8E6E1165DF7"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:5.13:rc2:*:*:*:*:*:*","matchCriteriaId":"96AC23B2-D46A-49D9-8203-8E1BEDCA8532"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:5.13:rc3:*:*:*:*:*:*","matchCriteriaId":"DA610E30-717C-4700-9F77-A3C9244F3BFD"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:5.13:rc4:*:*:*:*:*:*","matchCriteriaId":"1ECD33F5-85BE-430B-8F86-8D7BD560311D"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:5.13:rc5:*:*:*:*:*:*","matchCriteriaId":"CF351855-2437-4CF5-AD7C-BDFA51F27683"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:5.13:rc6:*:*:*:*:*:*","matchCriteriaId":"25A855BA-2118-44F2-90EF-EBBB12AF51EF"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/ce6e8bee7a3883e8008b30f5887dbb426aac6a35","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/e41a49fadbc80b60b48d3c095d9e2ee7ef7c9a8e","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/f6ed2357541612a13a5841b3af4dc32ed984a25f","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/ce6e8bee7a3883e8008b30f5887dbb426aac6a35","source":"af854a3a-2127-422b-91ae-364da2661108","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/e41a49fadbc80b60b48d3c095d9e2ee7ef7c9a8e","source":"af854a3a-2127-422b-91ae-364da2661108","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/f6ed2357541612a13a5841b3af4dc32ed984a25f","source":"af854a3a-2127-422b-91ae-364da2661108","tags":["Patch"]}]}}]}