{"cve":"CVE-2023-6660","nvd":{"published":"2023-12-13T09:15:34.730","modified":"2026-06-17T06:51:12.690","status":"Modified","description":"When a program running on an affected system appends data to a file via an NFS client mount, the bug can cause the NFS client to fail to copy in the data to be written but proceed as though the copy operation had succeeded.  This means that the data to be written is instead replaced with whatever data had been in the packet buffer previously.  Thus, an unprivileged user with access to an affected system may abuse the bug to trigger disclosure of sensitive information.  In particular, the leak is limited to data previously stored in mbufs, which are used for network transmission and reception, and for certain types of inter-process communication.\n\nThe bug can also be triggered unintentionally by system applications, in which case the data written by the application to an NFS mount may be corrupted.  Corrupted data is written over the network to the NFS server, and thus also susceptible to being snooped by other hosts on the network.\n\nNote that the bug exists only in the NFS client; the version and implementation of the server has no effect on whether a given system is affected by the problem.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N","score":6.5},"cwes":[],"references":["https://security.freebsd.org/advisories/FreeBSD-SA-23:18.nfsclient.asc","https://security.netapp.com/advisory/ntap-20240322-0002/","https://security.freebsd.org/advisories/FreeBSD-SA-23:18.nfsclient.asc","https://security.netapp.com/advisory/ntap-20240322-0002/"],"products":["freebsd:freebsd"],"source":"nvd","synced_at":"2026-10-19T21:42:34.585441961+00:00"},"epss":{"cve":"CVE-2023-6660","score":0.00622,"percentile":0.49827,"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."]}