CVE intelligence

CVE-2026-64544

Vulnerability intelligence

Published Jul 27, 2026Sources checked Oct 28, 2026

N/ACVSS not listedScore unavailable

What this means

Review the available evidence

CVE-2026-64544. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

What to do next

Remediation and response

Microsoft Security Response Center guidance

Vendor revision: Aug 7, 2026

CBL-Mariner Releases

Vendor-listed releases

6.6.145.2-1

CISA KEVNot listedBased on the latest collected catalog

EPSS0.2%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-64544?

In the Linux kernel, the following vulnerability has been resolved:

crypto: asymmetric_keys - fix OOB read in pefile_digest_pe_contents

pefile_digest_pe_contents() computes the trailing-data hash length as pelen - (hashed_bytes + certs_size). A crafted PE can make the addition exceed pelen, causing the unsigned subtraction to underflow to ~4 GiB.

This is passed to crypto_shash_update() which reads out of bounds and panics on unmapped vmalloc guard pages.

BUG: unable to handle page fault for address: ffffc900038d8000 Oops: Oops: 0000 [#1] SMP KASAN NOPTI RIP: 0010:sha256_blocks_generic (lib/crypto/sha256.c:152) Call Trace: <TASK> __sha256_update (lib/crypto/sha256.c:208) crypto_sha256_update (crypto/sha256.c:142) verify_pefile_signature (crypto/asymmetric_keys/verify_pefile.c:436) kexec_kernel_verify_pe_sig (kernel/kexec_file.c:151) __do_sys_kexec_file_load (kernel/kexec_file.c:406) do_syscall_64 (arch/x86/entry/syscall_64.c:94) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121) </TASK> Kernel panic - not syncing: Fatal exception

Validate that the addition does not overflow and the result does not exceed pelen before the subtraction. Return -ELIBBAD on failure.

Source: NVD