CVE-2026-64558
HIGH
Published Jul 29, 2026
Modified Jul 30, 2026
Description
In the Linux kernel, the following vulnerability has been resolved: s390/pkey: Check length in pkey_pckmo handler implementation Explicitly check the length of the target buffer in the pkey_pckmo implementation of the key_to_protkey() handler function. The handler function fails, if the generated output data exceeds the length of the provided target buffer.
Is your site exposed to CVE-2026-64558?
Run a free security scan — no signup, results in seconds.
CVSS v3.1 Score
7.8
HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS — Exploit Prediction
0.0012
Probability of exploitation
0.02%
Percentile rank
EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.
References
Other References
Frequently Asked Questions
What is CVE-2026-64558? +
In the Linux kernel, the following vulnerability has been resolved:
s390/pkey: Check length in pkey_pckmo handler implementation
Explicitly check the length of the target buffer in the pkey_pckmo
implementation of the key_to_protkey() handler function. The handler
function fails, if the generated output data exceeds the length of the
provided target buffer. It has a CVSS v3.1 base score of 7.8 (HIGH).
How severe is CVE-2026-64558? +
CVE-2026-64558 has a CVSS v3.1 score of 7.8 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0012, placing it in the 0th percentile for exploitation probability.
How do I check if I'm vulnerable to CVE-2026-64558? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.
