Vulnerability in Mercusys AC12 (CVE-2026-78862)
Summary
Vulnerability in Mercusys AC12 (CVE-2026-78862). Successful exploitation can lead to full system takeover.
Original description
The description as published by the source.
An issue in Mercusys AC12 V2 allows a local attacker to execute arbitrary code via the UART serial interface on the printed circuit board (PCB)
Source: NIST National Vulnerability Database NVD GitHub Advisory
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 CVE-2026-78862 has been found in Mercusys AC12.
Successful exploitation can lead to full system takeover. CVSS score: 6.8/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Mercusys AC12 CVE-2026-78862" on the vendor's site.
CVE-2026-78862 (Mercusys AC12) — CWE-1299 / CVSS v3 6.8
Attack vector: physical / unauthenticated / no user interaction
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.
A vulnerability (CWE-1299) exists in Mercusys AC12.
Check the vendor advisory for the affected versions of Mercusys AC12.
Severity: Medium (CVSS 6.8/10). Successful exploitation can lead to full system takeover.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Mercusys AC12 を使っているサービスとバージョンを洗い出す。
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2Post-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。
References
- web cve@mitre.org
- web cve@mitre.org
- web threadpoolx.gitbook.io
- web nvd.nist.gov
- web github.com