{"cve":"CVE-2025-38579","nvd":{"published":"2025-08-19T17:15:35.020","modified":"2026-07-30T06:23:28.233","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nf2fs: fix KMSAN uninit-value in extent_info usage\n\nKMSAN reported a use of uninitialized value in `__is_extent_mergeable()`\n and `__is_back_mergeable()` via the read extent tree path.\n\nThe root cause is that `get_read_extent_info()` only initializes three\nfields (`fofs`, `blk`, `len`) of `struct extent_info`, leaving the\nremaining fields uninitialized. This leads to undefined behavior\nwhen those fields are accessed later, especially during\nextent merging.\n\nFix it by zero-initializing the `extent_info` struct before population.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":["CWE-908"],"references":["https://git.kernel.org/stable/c/01b6f5955e0008af6bc3a181310d2744bb349800","https://git.kernel.org/stable/c/08e8ab00a6d20d5544c932ee85a297d833895141","https://git.kernel.org/stable/c/154467f4ad033473e5c903a03e7b9bca7df9a0fa","https://git.kernel.org/stable/c/44a79437309e0ee2276ac17aaedc71253af253a8","https://git.kernel.org/stable/c/cc1615d5aba4f396cf412579928539a2b124c8a0"],"products":["debian:debian_linux","linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:07:46.309729541+00:00"},"epss":{"cve":"CVE-2025-38579","score":0.00177,"percentile":0.07178,"date":"2026-10-31"},"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."]}