CVE-2025-39717 PUBLISHED CVSS 7.800000190734863 HIGH

In the Linux kernel, the following vulnerability has been resolved: open_tree_attr: do not allow id-mapping changes without OPEN_TREE_CLONE As described in commit 7a54947e727b ('Merge patch series "fs: allow changing idmappings"'), open_tree_attr(2) was necessary in order to allow for a detached mount to be created and have its idmappings changed without the risk of any racing threads operating on it. For this reason, mount_setattr(2) still does not allow for id-mappings to be changed. However, there was a bug in commit 2462651ffa76 ("fs: allow changing idmappings") which allowed users to bypass this restriction by calling open_tree_attr(2) *without* OPEN_TREE_CLONE. can_idmap_mount() prevented this bug from allowing an attached mountpoint's id-mapping from being modified (thanks to an is_anon_ns() check), but this still allows for detached (but visible) mounts to have their be id-mapping changed. This risks the same UAF and locking issues as described in the merge commit, and was likely unintentional.

EPSS 0.02% · 4.7th percentile

Risk Scores

CVSS v3.1
7.800000190734863
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score
0.02%
4.7th percentile

Affected Products

VendorProductVersions
linuxlinux_kernel6.15, 6.15, 6.15
LinuxLinux2462651ffa76b87f9c2e4403ef6e6b89b703fb2f, 6.17, 2462651ffa76b87f9c2e4403ef6e6b89b703fb2f

Timeline

References

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