{"cve":"CVE-2026-89707","nvd":{"published":"2026-09-11T20:19:58.017","modified":"2026-10-19T09:18:09.483","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: release path refs on follow_down() error\n\nnfsd_cross_mnt() initializes a local struct path with mntget() and\ndget() before calling follow_down(). On a negative return the error\narm jumps to out without releasing those references:\n\n    err = follow_down(&path, follow_flags);\n    if (err < 0)\n            goto out;\n\nfollow_down() never drops the caller's entry-time refs on any error\nsub-case; for example a pre-cross d_manage() failure leaves path\nuntouched, so the mntget()/dget() taken on entry survive the call.\n\nEvery other early-exit arm in nfsd_cross_mnt() (other-namespace\nreturn, IS_ERR(exp2), and the success tail after the swap) already\ncalls path_put(&path); the err < 0 arm is the lone omission. The\nleak inflates mnt_count and d_count on each failed cross-mount,\nblocking umount and pinning dentries against the shrinker, and is\nreachable by any authenticated NFS client through nfsd_lookup_dentry\nor the NFSv4 READDIR encode path.\n\nFix by calling path_put(&path) before the goto out in the err < 0\narm so the entry-time refs are released on all follow_down() error\nreturns.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":[],"references":["https://git.kernel.org/stable/c/085cfde7c2186acaad103f02d2c25435ad5224e9","https://git.kernel.org/stable/c/194316df81263519156ebe714c4a286bee00e5be","https://git.kernel.org/stable/c/2bc4343308d85ee4e0dd3877b384306c96f114c2","https://git.kernel.org/stable/c/467d56fd3ff57447a790c6dc3ede2d02a947d224","https://git.kernel.org/stable/c/6cba08dc1922140d260cfeb30bbda4ee1bf869d8"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:53:43.293028046+00:00"},"epss":{"cve":"CVE-2026-89707","score":0.00612,"percentile":0.48993,"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."]}