CVE-2026-72382
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.
Affected versions
Linux kernel versions
5.15
and later are affected. Fixed in
6.6.145,
6.12.97,
6.18.40,
7.1.5,
7.2-rc2
and their respective stable series.
References
5 totalFrequently asked questions
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What is CVE-2026-72382?
CVE-2026-72382 is a unscored severity Linux kernel vulnerability . It affects Linux kernel versions from 5.15 onward and has been patched in 6.6.145, 6.12.97, 6.18.40 and others. CVE-2026-72382 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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Is there a patch available for CVE-2026-72382?
Yes. CVE-2026-72382 has been patched. Fixed versions include 6.6.145, 6.12.97, 6.18.40 and others. If you are running Linux kernel 5.15 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-72382 actively exploited?
No. CVE-2026-72382 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.