Vulnerability in linux (DEBIAN-CVE-2026-64544)

Summary

Vulnerability in linux (DEBIAN-CVE-2026-64544). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 6.1.180-1 or later.

Original description

The description as published by the source.

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: __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) 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: OSV.dev (Open Source Vulnerabilities) OSV

Auto-generated summary

Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.

A vulnerability tracked as DEBIAN-CVE-2026-64544 has been found in linux.
Risk of unauthorized operations or information disclosure.
What to do: upgrade linux to 6.1.180-1 or later.
If unsure, ask your IT team or search "linux DEBIAN-CVE-2026-64544" on the vendor's site.

DEBIAN-CVE-2026-64544 (linux)
Patched: 6.1.180-1 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.

❓ What is the problem

A vulnerability (unclassified) exists in linux.

📍 Affected scope

Check the vendor advisory for the affected versions of linux.

🔥 Severity

Severity: ?. Risk of unauthorized operations or information disclosure.

🔧 How to fix

Update to 6.1.180-1.

🛡️ Workaround

Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.

🔍 Detection

Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'linux' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.

Response actions

Concrete steps and command examples for SOC/SRE teams to execute in order

1
Identify exposure identify
```
grep -r 'linux' . | grep -v node_modules
```
リポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で linux を grep し、稼働しているサービス・バージョンを把握する。
2
Apply patch patch
```
Upgrade linux to 6.1.180-1
```
ステージング環境で 6.1.180-1 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
3
Post-deployment verification verify
```
Confirm patched version is live in production
```
パッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。

Affected packages

Debian:12 linux

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.1.180-1"}]}]

Debian:13 linux

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.12.100-1"}]}]

Debian:14 linux

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"7.1.5-1"}]}]

Debian:12 linux-6.12

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.12.100-1~deb12u1"}]}]

References

advisory security-tracker.debian.org