{"cve":"CVE-2026-31449","nvd":{"published":"2026-04-22T14:16:38.933","modified":"2026-10-19T19:17:54.320","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\next4: validate p_idx bounds in ext4_ext_correct_indexes\n\next4_ext_correct_indexes() walks up the extent tree correcting\nindex entries when the first extent in a leaf is modified. Before\naccessing path[k].p_idx->ei_block, there is no validation that\np_idx falls within the valid range of index entries for that\nlevel.\n\nIf the on-disk extent header contains a corrupted or crafted\neh_entries value, p_idx can point past the end of the allocated\nbuffer, causing a slab-out-of-bounds read.\n\nFix this by validating path[k].p_idx against EXT_LAST_INDEX() at\nboth access sites: before the while loop and inside it. Return\n-EFSCORRUPTED if the index pointer is out of range, consistent\nwith how other bounds violations are handled in the ext4 extent\ntree code.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","score":7.8},"cwes":["CWE-125"],"references":["https://git.kernel.org/stable/c/01bf1e0b997d82c0e353b51ed74ef99698043c33","https://git.kernel.org/stable/c/10242e640b36b91ad03d25f3dc77854bbdff8358","https://git.kernel.org/stable/c/2acb5c12ebd860f30e4faf67e6cc8c44ddfe5fe8","https://git.kernel.org/stable/c/39d6e2b67651614bac0dc6592fa9836321910067","https://git.kernel.org/stable/c/407c944f217c17d4343148011acafebc604d55e1"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-21T03:43:09.190223697+00:00"},"epss":{"cve":"CVE-2026-31449","score":0.00147,"percentile":0.03857,"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."]}