CVE-2026-52944

Linux kernel: information disclosure

Risk score: 48/100
CVSS: 5.5 v3.1
Exploit chance (30 days): 0.1%
Published: 24 Jun 2026

Open in the live forecast Today's forecast

What to know

What it is: In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix FSCTL permission bypass by adding a permission check for FSCTL_SET_SPARSE FSCTL_SET_SPARSE in fsctl_set_sparse() modifies the file's sparse attribute and saves it through xattr without any permission checks. This exposes two issues: 1) A cl…
Affected: Linux kernel
Fix: Apply the vendor's security update; see the linked advisory.
Exploitation: No known exploitation

Story map

Story map: the flaws, the fix, how it unfolded and what it connects to. Boxes link to the record or article.

At a glance

Linux kernel: Amber, patch this week. In the Linux kernel, the following vulnerability has been resolved: ipv6: sr: restore network header before routing and forwarding ipv6_srh_rcv() runs with skb->data at the Segment Routing Header (SRH) while skb_network_header() points at the IPv6 header. When segments_left > 0, ipv6_srh_rcv() previously restored the …

The flaws

CVE-2026-52944: Information disclosure (CVSS 5.5 · EPSS 0%)
CVE-2026-98096: Out-of-bounds write (CVSS 7.4 · EPSS 1%)
CVE-2026-98115: Race condition (CVSS 8.8 · EPSS 0%)
CVE-2026-98117: Use-after-free (CVSS 7.8 · EPSS 0%)

The fix

Fix: Apply the vendor's security update; see the linked advisory.

Who is exposed: Linux kernel

Where it stands

No known exploitation

How it unfolded

6 Nov, Ubuntu security notices (official): USN-9002-1: Linux kernel (NVIDIA Tegra) vulnerabilities

Connects to

Same weakness: Out-of-bounds write (CWE-787). 399 other warnings in 30 days
Same product: Earlier Linux kernel warnings. 156 in the last 90 days

Why it is Yellow

CVSS 5.5 medium
On your watchlist: linux kernel
Named in a government or vendor bulletin

Government and vendor bulletins

USN-9002-1: Linux kernel (NVIDIA Tegra) vulnerabilities

References

Original description

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix FSCTL permission bypass by adding a permission check for FSCTL_SET_SPARSE FSCTL_SET_SPARSE in fsctl_set_sparse() modifies the file's sparse attribute and saves it through xattr without any permission checks. This exposes two issues: 1) A client on a read-only share can change the sparse attribute on files it opened, even though the share is read-only. Other FSCTL write operations already check test_tree_conn_flag(work->tcon, KSMBD_TREE_CONN_FLAG_WRITABLE), but FSCTL_SET_SPARSE does not. 2) Even on writable shares, clients without FILE_WRITE_DATA or FILE_WRITE_ATTRIBUTES access should not modify the sparse attribute. Similar handle-level checks exist in other functions but are missing here. Add both share-level writable check and per-handle access check. Use goto out on error to avoid leaking file references.

Last activity 6 Nov 2026. Patch Forecast updates every hour.