CVE-2026-53266(linux linux kernel)の深刻度・悪用状況・対象バージョン

8.8 重要(CVSS 3.x) 悪用確認済み(CISA KEV) EPSS 取得中…

概要

In the Linux kernel, the following vulnerability has been resolved: netfilter: bridge: make ebt_snat ARP rewrite writable The ebtables SNAT target keeps the Ethernet source address rewrite behind skb_ensure_writable(skb, 0). This is intentional: at the bridge ebtables hooks the Ethernet header is addressed through skb_mac_header()/eth_hdr(), while skb->data points at the Ethernet payload. Asking skb_ensure_writable() for ETH_HLEN bytes would check the payload, not the Ethernet header, and would reintroduce the small packet regression fixed by commit 63137bc5882a. However, the optional ARP sender hardware address rewrite is different. It writes through skb_store_bits() at an offset relative to skb->data: skb_store_bits(skb, sizeof(struct arphdr), info->mac, ETH_ALEN) skb_header_pointer() only safely reads the ARP header; it does not make the later sender hardware address range writable. If that range is still held in a nonlinear skb fragment backed by a splice-imported file page, skb_store_bits() maps the frag page and copies the new MAC address directly into it. Ensure the ARP SHA range is writable before reading the ARP header and before calling skb_store_bits().

実際の攻撃で悪用されています。 CISA KEV への追加日: 2026-09-18。対象製品を使っている場合は最優先で対策してください。
CISA の要求対応: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

影響を受ける製品

ベンダー製品対象バージョン
linuxlinux_kernel≥ 5.4.73 かつ < 5.5
linuxlinux_kernel≥ 5.8.17 かつ < 5.9
linuxlinux_kernel≥ 5.9.2 かつ < 5.10.259
linuxlinux_kernel≥ 5.11 かつ < 5.15.210
linuxlinux_kernel≥ 5.16 かつ < 6.1.176
linuxlinux_kernel≥ 6.2 かつ < 6.6.143
linuxlinux_kernel≥ 6.7 かつ < 6.12.94
linuxlinux_kernel≥ 6.13 かつ < 6.18.36
linuxlinux_kernel≥ 6.19 かつ < 7.0.13
linuxlinux_kernel7.1
linuxlinux_kernel7.1
linuxlinux_kernel7.1
linuxlinux_kernel7.1
linuxlinux_kernel7.1
linuxlinux_kernel7.1

基本情報

公開日
2026-06-25
最終更新
2026-09-19
NVD の状態
Analyzed
弱点の種類
CWE-787

対策の進め方

  1. 上の表で、使っている製品とバージョンが対象か確認します。
  2. ベンダーの公式アドバイザリ(下の参考情報の「Vendor Advisory」「Patch」)で修正版・回避策を確認します。
  3. 悪用が確認されているため、パッチ適用までの間もアクセス制限・侵害の痕跡確認を検討します。
  4. 日本語の情報は JVN iPedia で CVE-2026-53266 を検索 できます。

参考情報

データ出典: NIST NVD、CISA KEV、FIRST EPSS。翻訳は参考情報で、正確性は原文を優先してください。