{"id":"AZL-92600","summary":"CVE-2026-53393 affecting package kernel for versions less than 6.6.145.2-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: reset write verifier on deferred writeback errors\n\nnfsd_vfs_write() and nfsd_commit() both call filemap_check_wb_err() to\ndetect deferred writeback errors, but neither rotates the server's write\nverifier (nn-\u003ewriteverf) when this check fails. Every other\ndurable-storage-failure path in these functions calls\ncommit_reset_write_verifier() before returning an error.\n\nThe missing rotation means clients holding UNSTABLE write data under the\ncurrent verifier will COMMIT, receive the unchanged verifier back, and\nconclude their data is durable — silently dropping data that failed\nwriteback. This violates the UNSTABLE+COMMIT durability contract\n(RFC 1813 §3.3.7, RFC 8881 §18.32).\n\nAdd commit_reset_write_verifier() calls at both filemap_check_wb_err()\nerror sites, matching the pattern used by adjacent error paths in the\nsame functions. The helper already filters -EAGAIN and -ESTALE\ninternally, so the calls are unconditionally safe.","modified":"2026-08-28T17:47:39.098371658Z","published":"2026-07-19T12:16:50Z","upstream":["CVE-2026-53393"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-53393"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.6.145.2-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-92600.json"}}],"schema_version":"1.9.0"}