CVE-2026-64304: crypto: qat - validate RSA CRT component lengths

Severity: high (CVSS 7.8 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: 2026-07-25 · updated 2026-10-24
Weakness: CWE-787

Description

In the Linux kernel, the following vulnerability has been resolved: crypto: qat - validate RSA CRT component lengths The generic RSA key parser (rsa_helper.c) bounds each CRT component (p, q, dp, dq, qinv) by the modulus size n_sz, but qat_rsa_setkey_crt() allocates half-size DMA buffers (key_sz / 2) and right-aligns each component with: memcpy(dst + half_key_sz - len, src, len) When a CRT component is larger than half_key_sz the subtraction underflows and memcpy writes past the DMA buffer, causing memory corruption. Add a len > half_key_sz check next to the existing !len check for each of the five CRT components so the driver falls back to the non-CRT path instead of writing out of bounds.

Affected products

Linux kernel: from 4.8 before 5.10.261; from 5.11 before 5.15.212; from 5.16 before 6.1.178; from 6.2 before 6.6.145; from 6.7 before 6.12.96; from 6.13 before 6.18.39 — fixed in 5.10.261, 5.15.212, 6.1.178, 6.12.96, 6.18.39, 6.6.145

How to fix

Upgrade to a fixed version: Linux kernel 5.10.261, 5.15.212, 6.1.178, 6.12.96. Check the vendor advisory for mitigations.

References

Get alerted when CVE-2026-64304 or the next vulnerability affects your stack