smb: client: reject userspace cifs.idmap descriptions
Summary
| CVE | CVE-2026-97564 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-09-25 11:17:07 UTC |
| Updated | 2026-10-03 11:18:03 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: smb: client: reject userspace cifs.idmap descriptions cifs.idmap key descriptions carry authority-bearing fields (owner and group SIDs and uid/gid values in "os:"/"gs:"/"oi:"/"gi:" form) that the cifs.idmap upcall helper treats as kernel-originating inputs. Unlike its sibling cifs.spnego, the cifs.idmap key type has no vet_description hook, so userspace can create keys of this type through request_key(2)/add_key(2) and supply those fields without CIFS origin. A request_key(2) call with a non-NULL callout then drives a root usermodehelper upcall (/sbin/request-key -> cifs.idmap) that consumes the unvetted description in root context. Only accept cifs.idmap descriptions while CIFS is using its private root_cred to request the key. id_to_sid()/sid_to_id() already run under override_creds(root_cred), so the kernel-originated path is unaffected. This mirrors commit 3da1fdf4efbc ("smb: client: reject userspace cifs.spnego descriptions"), which applied the same restriction to cifs.spnego. |
Risk And Classification
EPSS: 0.002000000 probability, percentile 0.088990000 (date 2026-10-03)
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected 4d79dba0e00749fa40de8ef13a9b85ce57a1603b f29c1ec0e7d8c887a91df3f93bb4617c0ac95c6a git | Not specified |
| CNA | Linux | Linux | affected 4d79dba0e00749fa40de8ef13a9b85ce57a1603b 17c93bcd17755523c21abb22cbf2a41a6eb0caaf git | Not specified |
| CNA | Linux | Linux | affected 4d79dba0e00749fa40de8ef13a9b85ce57a1603b e5964064e3fbe6325893408faff08ca33de0e2c3 git | Not specified |
| CNA | Linux | Linux | affected 4d79dba0e00749fa40de8ef13a9b85ce57a1603b 96751028c0d4dec785709ea3eb0ab38a4f2ded96 git | Not specified |
| CNA | Linux | Linux | affected 4d79dba0e00749fa40de8ef13a9b85ce57a1603b 1d3b24b16a0b013792e8f1e3ed060f0b46f537d1 git | Not specified |
| CNA | Linux | Linux | affected 4d79dba0e00749fa40de8ef13a9b85ce57a1603b d9d7eeb0cea5b55b82888f443622fd8d4ee064f3 git | Not specified |
| CNA | Linux | Linux | affected 3.0 | Not specified |
| CNA | Linux | Linux | unaffected 3.0 semver | Not specified |
| CNA | Linux | Linux | unaffected 6.1.189 6.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.6.158 6.6.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.12.111 6.12.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.18.53 6.18.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.2.7 7.2.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.3-rc3 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/1d3b24b16a0b013792e8f1e3ed060f0b46f537d1 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/e5964064e3fbe6325893408faff08ca33de0e2c3 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/d9d7eeb0cea5b55b82888f443622fd8d4ee064f3 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/17c93bcd17755523c21abb22cbf2a41a6eb0caaf | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/f29c1ec0e7d8c887a91df3f93bb4617c0ac95c6a | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/96751028c0d4dec785709ea3eb0ab38a4f2ded96 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.