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.

Package Linux Kernel
Published 2026-07-27
Last modified 2026-07-27
Patch available
Yes

Affected versions

Linux kernel versions 3.17 and later are affected. Fixed in 5.10.261, 5.15.212, 6.1.178, 6.6.145, 6.12.97, 6.18.40, 7.1.5, 7.2-rc1 and their respective stable series.

Affected from
≥ 3.17
Fixed in
✓ 5.10.261 5.10.x ✓ 5.15.212 5.15.x ✓ 6.1.178 6.1.x ✓ 6.6.145 6.6.x ✓ 6.12.97 6.12.x ✓ 6.18.40 6.18.x ✓ 7.1.5 7.1.x ✓ 7.2-rc1

Frequently asked questions

  • What is CVE-2026-64544?

    CVE-2026-64544 is a unscored severity Linux kernel vulnerability . It affects Linux kernel versions from 3.17 onward and has been patched in 5.10.261, 5.15.212, 6.1.178 and others. CVE-2026-64544 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

  • Is there a patch available for CVE-2026-64544?

    Yes. CVE-2026-64544 has been patched. Fixed versions include 5.10.261, 5.15.212, 6.1.178 and others. If you are running Linux kernel 3.17 or later up to the fix versions, apply the relevant patch for your kernel branch.

  • Is CVE-2026-64544 actively exploited?

    No. CVE-2026-64544 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.