CVE-2026-63837
net: ena: PHC: Check return code before setting timestamp output
Description
In the Linux kernel, the following vulnerability has been resolved: net: ena: PHC: Check return code before setting timestamp output ena_phc_gettimex64() is setting the output parameter regardless of whether ena_com_phc_get_timestamp() succeeded or failed. When ena_com_phc_get_timestamp() returns an error, the timestamp parameter may contain uninitialized stack memory (e.g., when PHC is disabled or in blocked state) or invalid hardware values. Passing these to userspace via the PTP ioctl is both a security issue (information leak) and a correctness bug. Fix by checking the return code after releasing the lock and only setting the output timestamp on success.
INFO
Published Date :
July 19, 2026, 3:16 p.m.
Last Modified :
July 19, 2026, 3:16 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products
The following products are affected by CVE-2026-63837
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
- Verify return code before setting timestamp output.
- Update the Linux kernel to the patched version.
- Ensure PHC is enabled and not blocked.
- Avoid passing invalid hardware values to userspace.
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-2026-63837.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-63837 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-2026-63837
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-2026-63837 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-63837 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.
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New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Jul. 19, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': 'e0ea34158ee8c4f7536cd781010339ff28c0d24c', 'lessThan': 'bddf59818ae5102e6d82a4dae5add6df8da38fb0', 'versionType': 'git'}, {'status': 'affected', 'version': 'e0ea34158ee8c4f7536cd781010339ff28c0d24c', 'lessThan': 'edcb049d836e175e7b3d5e0d05657104545b5e65', 'versionType': 'git'}, {'status': 'affected', 'version': 'e0ea34158ee8c4f7536cd781010339ff28c0d24c', 'lessThan': '24a08d7d6218d60c033015cf4870b6096446e734', 'versionType': 'git'}], 'programFiles': ['drivers/net/ethernet/amazon/ena/ena_phc.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.17'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.17', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.18.33', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.0.10', 'versionType': 'semver', 'lessThanOrEqual': '7.0.*'}, {'status': 'unaffected', 'version': '7.1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['drivers/net/ethernet/amazon/ena/ena_phc.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: net: ena: PHC: Check return code before setting timestamp output ena_phc_gettimex64() is setting the output parameter regardless of whether ena_com_phc_get_timestamp() succeeded or failed. When ena_com_phc_get_timestamp() returns an error, the timestamp parameter may contain uninitialized stack memory (e.g., when PHC is disabled or in blocked state) or invalid hardware values. Passing these to userspace via the PTP ioctl is both a security issue (information leak) and a correctness bug. Fix by checking the return code after releasing the lock and only setting the output timestamp on success. Added Reference https://git.kernel.org/stable/c/24a08d7d6218d60c033015cf4870b6096446e734 Added Reference https://git.kernel.org/stable/c/bddf59818ae5102e6d82a4dae5add6df8da38fb0 Added Reference https://git.kernel.org/stable/c/edcb049d836e175e7b3d5e0d05657104545b5e65