{"cve":"CVE-2025-21836","nvd":{"published":"2025-03-07T09:15:16.600","modified":"2026-10-15T22:18:09.957","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring/kbuf: reallocate buf lists on upgrade\n\nIORING_REGISTER_PBUF_RING can reuse an old struct io_buffer_list if it\nwas created for legacy selected buffer and has been emptied. It violates\nthe requirement that most of the field should stay stable after publish.\nAlways reallocate it instead.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":[],"references":["https://git.kernel.org/stable/c/146a185f6c05ee263db715f860620606303c4633","https://git.kernel.org/stable/c/2a5febbef40ce968e295a7aeaa5d5cbd9e3e5ad4","https://git.kernel.org/stable/c/7d0dc28dae836caf7645fef62a10befc624dd17b","https://git.kernel.org/stable/c/8802766324e1f5d414a81ac43365c20142e85603","https://u1f383.github.io/slides/talks/2025_Hexacon-Deja_Vu_in_Linux_io_uring_Breaking_Memory_Sharing_Again_After_Generations_of_Fixes.pdf"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:00:17.429720821+00:00"},"epss":{"cve":"CVE-2025-21836","score":0.00252,"percentile":0.16495,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}