Multiple DrayTek VigorSwitch models contain a null pointer dereference vulnerability in the...
Summary
Vulnerability reported (CVE-2026-71920). Risk of unauthorized operations or information disclosure. Exploitable via Cookie header.
Original description
The description as published by the source.
Multiple DrayTek VigorSwitch models contain a null pointer dereference vulnerability in the formlogout function. The vulnerability is caused by missing checks for an empty or absent Cookie header before string handling. A remote attacker can trigger this vulnerability via a crafted request to crash the service and cause a denial of service. Exploitation requires valid administrative credentials for the device's web management interface.
Source: GitHub Security Advisories (Global) 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-2026-71920 has been found.
Attackers can target a specific entry point like Cookie header over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 4.9/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "CVE-2026-71920" on the vendor's site.
CVE-2026-71920 — CWE-476 / CVSS v3 4.9
Attack vector: remote (network-reachable) / no user interaction
Attack surface: Cookie header
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-476) has been reported. Attackers reach the vulnerable code path via Cookie header.
Check the vendor advisory for the affected versions. Attack surface: Cookie header.
Severity: Medium (CVSS 4.9/10). Risk of unauthorized operations or information disclosure.
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影響コンポーネントを特定する。
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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 nvd.nist.gov
- web draytek.com
- web disclosure@vulncheck.com
- web github.com
- web disclosure@vulncheck.com