CVE-2026-98388

exec: do_close_on_exec() before taking exec_update_lock

Published Oct 14, 2026 CVSS 3.1 · 5.5 Medium EPSS < 1% KEV · Not listed
Description
In the Linux kernel, the following vulnerability has been resolved:

exec: do_close_on_exec() before taking exec_update_lock

do_close_on_exec() currently happens while holding the exec_update_lock,
which is used in a lot of places that access process state to
synchronize access checks.
I recently added another such use of exec_update_lock, causing a
regression.

do_close_on_exec() can block waiting for a reply from a filesystem.
That means a hung filesystem can block codepaths that use
exec_update_lock; and it also means that a FUSE filesystem which
attempts to inspect the calling process can deadlock.

To avoid such problems, move do_close_on_exec() before the
exec_update_lock is taken, but after the FD table has been copied if
necessary.

I have looked through all the calls between the old and new position of
the do_close_on_exec() call; there seems to be no file descriptor table
access in between.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Debian DLA Debian DLA DLA-4841-1 linux security update
Ubuntu USN Ubuntu USN USN-8961-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-9019-1 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-9020-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-9022-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-9023-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-9039-1 Linux kernel (Azure CVM) vulnerabilities
History
Type Values Removed Values Added
Weaknesses CWE-613
Type Values Removed Values Added
Weaknesses CWE-833
References
Metrics threat_severity

None

cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Low

Type Values Removed Values Added
Weaknesses CWE-613
Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: exec: do_close_on_exec() before taking exec_update_lock do_close_on_exec() currently happens while holding the exec_update_lock, which is used in a lot of places that access process state to synchronize access checks. I recently added another such use of exec_update_lock, causing a regression. do_close_on_exec() can block waiting for a reply from a filesystem. That means a hung filesystem can block codepaths that use exec_update_lock; and it also means that a FUSE filesystem which attempts to inspect the calling process can deadlock. To avoid such problems, move do_close_on_exec() before the exec_update_lock is taken, but after the FD table has been copied if necessary. I have looked through all the calls between the old and new position of the do_close_on_exec() call; there seems to be no file descriptor table access in between.
Title exec: do_close_on_exec() before taking exec_update_lock
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
Linux
Published
Updated
Oct 19, 2026, 9:18 AM
Reserved
Sep 25, 2026, 10:25 AM
Status
Received
Published
Oct 14, 2026, 2:17 PM
Modified
Oct 19, 2026, 10:18 AM
Severity
Low
Public date
Oct 14, 2026, 12:00 AM