CVE-2026-64101: fwctl: pds: Validate RPC input size before parsing

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-07-19 · updated 2026-08-11

Description

In the Linux kernel, the following vulnerability has been resolved: fwctl: pds: Validate RPC input size before parsing The fwctl core allocates the device-specific RPC input buffer with fwctl_rpc.in_len and passes that buffer to the driver callback. pdsfc_fw_rpc() casts the buffer to struct fwctl_rpc_pds and then calls pdsfc_validate_rpc(), which reads fields from that structure before checking that the input buffer is large enough to contain it. A short in_len can make pds_fwctl read beyond the allocation. Reject pds RPC buffers that are smaller than struct fwctl_rpc_pds before parsing any pds-specific fields.

Affected products

Linux kernel: from 6.15 before 6.18.34; from 6.19 before 7.0.11; 7.1-rc1, 7.1-rc2, 7.1-rc3, 7.1-rc4 — fixed in 6.18.34, 7.0.11

How to fix

Upgrade to a fixed version: Linux kernel 6.18.34, 7.0.11. Check the vendor advisory for mitigations.

References

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