CVE-2026-58084

Kernel stack disclosure via timer_settime(2)

Published Aug 19, 2026 CVSS 3.1 · 5.5 Medium EPSS < 1% KEV · Not listed
Description
To retrieve the previous timer value, the kernel calls realtimer_gettime(), which obtains the current time for the timer's clock. For a timer using CLOCK_TAI this can fail when no TAI offset has been configured, but the error return was not checked, so the uninitialized output buffer was copied to userspace.

An unprivileged local user can obtain uninitialized kernel stack memory by creating a POSIX timer with CLOCK_TAI and calling timer_settime(2), potentially disclosing sensitive kernel data.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

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History
Type Values Removed Values Added
CPEs cpe:2.3:o:freebsd:freebsd:15.0:-:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:15.0:p10:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:15.0:p11:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:15.0:p1:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:15.0:p2:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:15.0:p3:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:15.0:p4:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:15.0:p5:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:15.0:p6:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:15.0:p7:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:15.0:p8:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:15.0:p9:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:15.1:-:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:15.1:p1:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:15.1:rc2:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:15.1:rc3-p1:*:*:*:*:*:*
Type Values Removed Values Added
Metrics cvssV3_1

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

ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Freebsd
Freebsd freebsd
Vendors & Products Freebsd
Freebsd freebsd
Type Values Removed Values Added
Description To retrieve the previous timer value, the kernel calls realtimer_gettime(), which obtains the current time for the timer's clock. For a timer using CLOCK_TAI this can fail when no TAI offset has been configured, but the error return was not checked, so the uninitialized output buffer was copied to userspace. An unprivileged local user can obtain uninitialized kernel stack memory by creating a POSIX timer with CLOCK_TAI and calling timer_settime(2), potentially disclosing sensitive kernel data.
Title Kernel stack disclosure via timer_settime(2)
Weaknesses CWE-908
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
freebsd
Published
Updated
Aug 26, 2026, 7:46 PM
Reserved
Jun 29, 2026, 1:40 AM
Status
Analyzed
Published
Aug 19, 2026, 8:17 AM
Modified
Oct 27, 2026, 12:10 PM