CVE-2026-80545
Received
Received - Intake
Improper Input Validation in Linux Kernel s390/zcrypt
Vulnerability report for CVE-2026-80545, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-08-26
Last updated on: 2026-08-26
Assigner: kernel.org
Description
Description
In the Linux kernel, the following vulnerability has been resolved:
s390/zcrypt: Improve EP11 CPRB length and overflow checks
The xcrb_msg_to_type6_ep11cprb_msgx() function lacks proper input
validation, creating security vulnerabilities:
1. Missing minimum size validation: The ep11_cprb structure and
subsequent payload fields (pld_tag, pld_lenfmt) are copied from
userspace without verifying sufficient buffer length.
2. Arithmetic overflow in length calculations: CEIL4 alignment could
overflow, bypassing size checks and enabling buffer overflows.
3. The payload is asn1 encoded but the function just uses a simple c
struct overlay to access some fields of the payload.
Fix by using size_t for length calculations, adding U32_MAX boundary
checks after alignment, and validating minimum request size and
minimum reply size before copying from userspace. Do a very simple
asn1 parsing of the payload up to the function value field.
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| linux | linux_kernel | * |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-UNKNOWN |
