# CVE-2026-99113: ksmbd: zero the FS_OBJECT_ID_INFORMATION buffer before filling it in

CVE-2026-99113 is fixed in linux on 1 platform, first by DEBIAN-CVE-2026-99113, released November 3, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-99113
- Priority: Routine
- CVSS: 3.1 (Low)
- EPSS: 0.0017
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Oct 28, 2026
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-99113

## Description

In the Linux kernel, the following vulnerability has been resolved:  ksmbd: zero the FS_OBJECT_ID_INFORMATION buffer before filling it in  smb2_get_info_filesystem() reports 64 bytes for FS_OBJECT_ID_INFORMATION, that is the whole of struct object_id_info, but writes only 46 of them:   - objid[] is 16 bytes, and when the volume UUID is not available only    sizeof(stfs.f_fsid) (8) bytes are copied into it;  - extended_info.version_string[] is STRING_LENGTH (28) bytes, and only    strlen("1.1.0") (5) bytes are copied into it.  The response buffer is zeroed on allocation (kvzalloc() in smb2_allocate_rsp_buf()), so for a standalone request the remaining 31 bytes are zero.  In a compound request they need not be.  The offset of the next response is advanced by the length pinned for the previous one, so if a preceding command wrote its reply into the buffer and then failed, smb2_set_err_rsp() pins only the short error response and the next reply lands inside the area that has already been written.  Only the header is cleared there:  	memset((char *)rsp_hdr, 0, sizeof(struct smb2_hdr) + 2);  The client then receives up to 31 bytes of a response it was not meant to see, including one that failed with an access denied error.  Clear the structure before filling it in.  As a side effect version_string is now NUL terminated.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 13.5 (trixie) | 6.12.115-2 | [DEBIAN-CVE-2026-99113](https://patchblox.com/security/data/fix/linux/debian-cve-2026-99113.md) | Nov 3, 2026 |
| Linux | linux Debian 14 | 7.2.13-1 | [DEBIAN-CVE-2026-99113](https://patchblox.com/security/data/fix/linux/debian-cve-2026-99113.md) | Nov 3, 2026 |

---

Data as of 2026-11-08T06:59:42Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

Free to use with attribution: show "Data: Patchblox Patch Radar" with a link to https://patchblox.com/security/patch-radar. Terms, including what needs a written agreement: https://patchblox.com/security/patch-radar/use-the-data

Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.