{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-68243","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2025-12-16T13:41:40.263Z","datePublished":"2025-12-16T14:21:20.421Z","dateUpdated":"2026-08-05T12:10:25.864Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-05T12:10:25.864Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nNFS: Check the TLS certificate fields in nfs_match_client()\n\nIf the TLS security policy is of type RPC_XPRTSEC_TLS_X509, then the\ncert_serial and privkey_serial fields need to match as well since they\ndefine the client's identity, as presented to the server."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The vulnerable matching occurs during local NFS client setup or an internal referral/pNFS automount. A local attacker can consume an incorrectly credentialed mount, but arbitrary network packets alone cannot create the required client collision.\nAC:H - Exploitation requires a pre-existing mTLS client in the same network namespace with matching endpoint, protocol, NFS version, and minor version but a different, more privileged certificate, created in the favorable order. These deployment conditions are outside an unprivileged attacker’s control.\nPR:L - Directly creating the conflicting mount requires initial-user-namespace CAP_SYS_ADMIN because affected NFS filesystems lack FS_USERNS_MOUNT. However, an ordinary local user with access to an administrator-created misbound mount can exploit the stronger certificate identity.\nUI:N - Once the conflicting mounts or internal NFS clients exist, the attacker can access the misbound mount directly without another user taking an action.\nS:U - The flaw changes which NFS client identity the kernel presents but does not cross a VM, IOMMU, or sandbox security boundary.\nC:H - Reusing a more privileged client certificate can bypass server-side certificate authorization and expose entire sensitive NFS exports to unauthorized reads.\nI:H - If the inherited certificate authorizes write access, the attacker can modify or delete arbitrary data throughout protected NFS exports.\nA:H - The stronger identity can authorize destructive operations against service-critical exports, permitting deletion or corruption that makes the hosted data or dependent services unavailable."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/nfs/client.c"],"versions":[{"version":"90c9550a8d65fb9b1bf87baf97a04ed91bf61b33","lessThan":"b8fa37219074811c04d4ecb742c73e2b296da6a8","status":"affected","versionType":"git"},{"version":"90c9550a8d65fb9b1bf87baf97a04ed91bf61b33","lessThan":"fb2cba0854a7f315c8100a807a6959b99d72479e","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/nfs/client.c"],"versions":[{"version":"6.17","status":"affected"},{"version":"0","lessThan":"6.17","status":"unaffected","versionType":"semver"},{"version":"6.17.9","lessThanOrEqual":"6.17.*","status":"unaffected","versionType":"semver"},{"version":"6.18","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.17","versionEndExcluding":"6.17.9"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.17","versionEndExcluding":"6.18"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/b8fa37219074811c04d4ecb742c73e2b296da6a8"},{"url":"https://git.kernel.org/stable/c/fb2cba0854a7f315c8100a807a6959b99d72479e"}],"title":"NFS: Check the TLS certificate fields in nfs_match_client()","x_generator":{"engine":"bippy-1.2.0"}}}}