{"cve":"CVE-2026-46169","nvd":{"published":"2026-05-28T10:16:32.537","modified":"2026-06-19T13:16:34.600","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nhfsplus: fix uninit-value by validating catalog record size\n\nSyzbot reported a KMSAN uninit-value issue in hfsplus_strcasecmp(). The\nroot cause is that hfs_brec_read() doesn't validate that the on-disk\nrecord size matches the expected size for the record type being read.\n\nWhen mounting a corrupted filesystem, hfs_brec_read() may read less data\nthan expected. For example, when reading a catalog thread record, the\ndebug output showed:\n\n  HFSPLUS_BREC_READ: rec_len=520, fd->entrylength=26\n  HFSPLUS_BREC_READ: WARNING - entrylength (26) < rec_len (520) - PARTIAL READ!\n\nhfs_brec_read() only validates that entrylength is not greater than the\nbuffer size, but doesn't check if it's less than expected. It successfully\nreads 26 bytes into a 520-byte structure and returns success, leaving 494\nbytes uninitialized.\n\nThis uninitialized data in tmp.thread.nodeName then gets copied by\nhfsplus_cat_build_key_uni() and used by hfsplus_strcasecmp(), triggering\nthe KMSAN warning when the uninitialized bytes are used as array indices\nin case_fold().\n\nFix by introducing hfsplus_brec_read_cat() wrapper that:\n1. Calls hfs_brec_read() to read the data\n2. Validates the record size based on the type field:\n   - Fixed size for folder and file records\n   - Variable size for thread records (depends on string length)\n3. Returns -EIO if size doesn't match expected\n\nFor thread records, check against HFSPLUS_MIN_THREAD_SZ before reading\nnodeName.length to avoid reading uninitialized data at call sites that\ndon't zero-initialize the entry structure.\n\nAlso initialize the tmp variable in hfsplus_find_cat() as defensive\nprogramming to ensure no uninitialized data even if validation is\nbypassed.","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":["CWE-908"],"references":["https://git.kernel.org/stable/c/3003dbf62d151d47a6b90f71655292a51a05f244","https://git.kernel.org/stable/c/3bc337697c66db2e2a4a94f0509c282c1a014b86","https://git.kernel.org/stable/c/61a790974ff7e533acbceca06c7d02f22bf96d4d","https://git.kernel.org/stable/c/8be69532e399eec9d9d990f6958b4ff2383b19b3","https://git.kernel.org/stable/c/93e8d613f1a01b6637f387cc93f184cf7fb881d6"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:36:28.938604137+00:00"},"epss":{"cve":"CVE-2026-46169","score":0.0013,"percentile":0.02629,"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."]}