CVE-2026-93811

ksmbd: Fix acl.sd_buf memory leak and invalid sd_size error handling

N/A

Published: September 24, 2026 at 04:02 PM UTC

Updated: October 3, 2026 at 11:17 AM UTC

1 product affected across 1 vendorLinux Kernel

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Severity

N/A

Exploit prediction

EPSS 0.2%

Description

In the Linux kernel, the following vulnerability has been resolved: ksmbd: Fix acl.sd_buf memory leak and invalid sd_size error handling 1. When ndr_decode_v4_ntacl() fails, the code jumped to free_n_data which only freed n.data, skipping kfree(acl.sd_buf) and leaking the buffer. Zero-initialize struct xattr_ntacl acl, reorder error labels to out_free to release acl.sd_buf on all error paths. 2. if (acl.sd_size < sizeof(struct smb_ntsd)) is true, original code returned success without freeing sd_buf and left stale *pntsd. Set rc = -EINVAL before jumping to out_free to return error code and free buffer.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Linux Kernel · Linux

95%

v ≥ 5.18.18v ≥ 5.19.25.15.62 ≤ v < 5.15.2225.18.18 ≤ v < 5.195.19.2 ≤ v < 5.206.0 ≤ v < 6.1.1896.0 ≤ v < 6.12.1116.0 ≤ v < 6.18.536.0 ≤ v < 6.6.1586.0 ≤ v < 7.25.15.62 5.18.18 5.19.2 6.06e8f4abf584253cbaa596ea4ad13110cf61cd4c98e33102309bd6839b2e2e158f93a7b378cb4655d8f0541186e9ad1b62accc9519cc2b7a7240272a7cb69d4d6f709f87c94afa28ae64c501576692171

Vendor states this is fixed in 6e6329322ad733c5b23555c609353841560b26bc (fixed)

Vendor states this is fixed in 86c2625fb9863139b359805fc6be1e31edbd3d65 (fixed)

Vendor states this is fixed in c3836f55e0dab96314774215e12d87f63fa919f2 (fixed)

Vendor states this is fixed in d708a36634bb7b6f94d0e76d587d2ec50b2b93b5 (fixed)

Vendor states this is fixed in edc17db83085624a2b1bacf6a4521d7f15571737 (fixed)

Vendor states this is fixed in f46a70a082bdbfecbe074af8a719c26c4deb58c6 (fixed)

Vendor states this is fixed in 5.15.222 (unaffected)

Affected range stops below 5.19, so it looks safe — our inference, not a vendor statement

Affected range stops below 5.20, so it looks safe — our inference, not a vendor statement

Vendor states this is fixed in 6.0 (unaffected)

Vendor states this is fixed in 6.1.189 (unaffected)

Vendor states this is fixed in 6.12.111 (unaffected)