# CVE-2026-72382: linux: In the Linux kernel, the following vulnerability has been resolved:  ksmbd: reject undersized DACLs before parsing AC...

CVE-2026-72382 is fixed in linux on 1 platform, first by DEBIAN-CVE-2026-72382, released August 15, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-72382
- Priority: High
- CVSS: 8.8 (high)
- EPSS: 0.0068
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Aug 15, 2026

## Description

In the Linux kernel, the following vulnerability has been resolved:  ksmbd: reject undersized DACLs before parsing ACEs  parse_dacl() limits the attacker-controlled ACE count by comparing it with the number of minimal ACEs that fit in the DACL size. The DACL size field is 16 bits, but the expression subtracts sizeof(struct smb_acl). Because sizeof() is unsigned, a DACL size smaller than the ACL header underflows to a large size_t.  A malicious client can reach this with:  SMB2_SET_INFO (InfoType=SMB2_O_INFO_SECURITY)   -> smb2_set_info_sec()   -> set_info_sec()   -> parse_sec_desc()   -> parse_dacl()      -> init_acl_state(..., 0xffff)      -> init_acl_state(..., 0xffff)      -> kmalloc_objs(..., 0xffff)  Thus a malformed security descriptor can make num_aces pass the guard and drive large temporary ACL state and pointer-array allocations.  Reject DACLs smaller than struct smb_acl before doing the subtraction, so the ACE count check cannot be bypassed by the underflow.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 13.5 (trixie) | 6.12.100-1 | [DEBIAN-CVE-2026-72382](https://patchblox.com/security/data/fix/linux/debian-cve-2026-72382.md) | Aug 15, 2026 |
| Linux | linux Debian 14 | 7.1.5-1 | [DEBIAN-CVE-2026-72382](https://patchblox.com/security/data/fix/linux/debian-cve-2026-72382.md) | Aug 15, 2026 |

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Data as of 2026-11-09T13:31:49Z 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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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