Vulnerability record

CVE-2020-14993

A permanent, source-backed tracker page. Values are shown only when returned; explicit gaps and read failures remain different states.

Full record read. Reported values and explicit gaps below come from the tracked record. Tracker snapshot: Aug 9, 2026.

What it is

Reported

A stack-based buffer overflow on DrayTek Vigor2960, Vigor3900, and Vigor300B devices before 1.5.1.1 allows remote attackers to execute arbitrary code via the formuserphonenumber parameter in an authusersms action to mainfunction.cgi. Source description excerpt; complete tracked detail loads below.

NVD published: Jun 23, 2020 · Source record updated: Aug 9, 2026 · Tracker snapshot: Aug 9, 2026

What is affected

Reported

DrayTek — vigor300b_firmware. Product-level identification only; no affected-version conclusion is available from this field.

NVD published: Jun 23, 2020 · Source record updated: Aug 9, 2026 · Tracker snapshot: Aug 9, 2026

Urgency and basis

Reported

Act · 456.7

Tracker decision tier from the evidence detailed below · Source record updated: Aug 9, 2026 · Tracker snapshot: Aug 9, 2026

Exploitation evidence

Reported

kev-listed · VulnCheck KEV

VulnCheck KEV added: Aug 22, 2025 · Source record updated: Aug 9, 2026 · Tracker snapshot: Aug 9, 2026

What to do

Reported

Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.

Source remediation ↗

Tracked source remediation field · Source record updated: Aug 9, 2026 · Tracker snapshot: Aug 9, 2026

Evidence detail

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