CVE-2020-28373: upnpd on certain NETGEAR devices allows remote (LAN) attackers to execute arbitrary code via a stack-based buffer overflow

Recommended actionWithin 7 days

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

Fix not verified

What, why and how

upnpd on certain NETGEAR devices allows remote (LAN) attackers to execute arbitrary code via a stack-based buffer overflow. This affects R6400v2 V1.0.4.102_10.0.75, R6400 V1.0.1.62_1.0.41, R7000P V1.3.2.126_10.1.66, XR300 V1.0.3.50_10.3.36, R8000 V1.0.4.62, R8300 V1.0.2.136, R8500 V1.0.2.136, R7300DST V1.0.0.74, R7850 V1.0.5.64, R7900 V1.0.4.30, RAX20 V1.0.2.64, RAX80 V1.0.3.102, and R6250 V1.0.4.44.

What

Why

A bounds error lets data be written beyond the intended memory region, potentially corrupting control data.

How

An attacker operating through the affected interface may attempt exploitation without authentication or user interaction. If successful, the issue may execute code or commands in the affected security context.

What

Why

A bounds error lets data be written beyond the intended memory region, potentially corrupting control data.

How

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation

Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.

No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material

Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.

None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path: the affected interface → Out-of-bounds Write → execute code or commands in the affected security context
Attack surface: Unspecified
Privileges required: None: unauthenticated exploitation is possible
User interaction: None
Attack complexity: Low: no specialised conditions are recorded
Security boundary: Unchanged: impact remains within the vulnerable component's security authority
Weakness ? CWE means Common Weakness Enumeration: a standard category for the underlying weakness.: CWE-787 ↗
CWE-787: Out-of-bounds Write. The product writes data past the end, or before the beginning, of the intended buffer.
CVSS vector ? CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.
AVAdjacentAttack vector: The attacker must be on an adjacent or logically close network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CHighConfidentiality impact: A successful attack can cause a major loss.IHighIntegrity impact: A successful attack can cause a major loss.AHighAvailability impact: A successful attack can cause a major loss.
Post-exploitation / living off the land: After compromise, an attacker may use built-in shells, scripting engines, scheduled tasks and native network utilities for discovery, persistence or movement. This is a plausible LoTL path, not evidence that it has occurred for every attack.

UnauthenticatedRemote code executionCWE-787

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

ENISA EUVD · EUVD-2020-20832Official EUVD mapping

0 linked advisory records.

Official EUVD record ↗

Cyber Security Agency of Singapore · English · CSA-SB-20201111Security Bulletin 11 Nov 2020

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 11 Nov 2020, published on 11 November 2020. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗

JVN iPedia · Japanese · JVNDB-2020-013349複数の NETGEAR デバイスにおける境界外書き込みに関する脆弱性

複数の NETGEAR デバイスには、境界外書き込みに関する脆弱性が存在します。

Official advisory ↗

Patch and workaround

Operational remediation based on structured source evidence.

Status ? Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.: Fix not verified
Affected: n/a
Fixed: No fixed version is explicitly recorded in the structured CVE data.
Action: No verified patch reference is present in the current structured sources. Check the vendor advisory before making a change.
Workaround: No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.

Evidence and provenance

Published 9 Nov 2020 · Last source change 4 Aug 2024, 16:33 UTC · CWE-787 · Out-of-bounds Write

CVE recordCVE.org · 5.1

CVSS sourceNIST NVD

EPSS source

The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.

FIRST · tracked since 2026-08-14

European sourceENISA EUVD · EUVD-2020-20832

Product sourceUnavailable

Remediation sourceCVE/CNA references

CWE sourceNIST NVD

NVD statusNVD modified after enrichment

Missing structured fields: affected product. Missing data is not evidence of low risk; review the primary advisory.

Material change intelligence

What changed after publication

View recent updates ↗

No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.

2020-11-09CVE published

ENISA EUVD · EUVD-2020-20832↗CVE authority or vendor reference↗Official CVE record (CNA and ADP data)↗NVD record↗

Technical terms and abbreviations used in this report

CVE: Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS: Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS: Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE: Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA: CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP: Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD: National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT: A computer security incident response team that publishes warnings or coordinates incident response.
PoC: Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF: Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL: Living off the land: abuse of legitimate tools or system functions during an attack.

upnpd on certain NETGEAR devices allows remote (LAN) attackers to execute arbitrary code via a stack-based buffer overflow

Published severity in operational context

Evidence used

Compensating controls

Verification

National CERT insights
?
CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

ENISA European Vulnerability Database

EUVD-2020-20832