CVE-2026-58084
Kernel stack disclosure via timer_settime(2)
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.
INFO
Published Date :
Aug. 19, 2026, 8:17 a.m.
Last Modified :
Aug. 19, 2026, 8:17 a.m.
Remotely Exploit :
No
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-58084
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
Solution
- Validate return codes from kernel time functions.
- Ensure TAI offset is configured before use.
- Check for uninitialized memory copies.
- Apply kernel updates when available.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-58084.
| URL | Resource |
|---|---|
| https://security.freebsd.org/advisories/FreeBSD-SA-26:51.ktimer.asc |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-58084 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-58084
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-58084 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-58084 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Aug. 19, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'FreeBSD', 'modules': ['ktimer'], 'product': 'FreeBSD', 'versions': [{'status': 'affected', 'version': '15.1-RELEASE', 'lessThan': 'p2', 'versionType': 'release'}, {'status': 'affected', 'version': '15.0-RELEASE', 'lessThan': 'p12', 'versionType': 'release'}], 'defaultStatus': 'unknown'}] 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. Added CWE CWE-908 Added Reference https://security.freebsd.org/advisories/FreeBSD-SA-26:51.ktimer.asc