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Full vulnerability report · 2020
CVE-2020-3451High confidence

Cisco Small Business RV340 Series Routers Command Injection and Remote Code Execution Vulnerabilities

Cisco · Cisco Small Business RV Series Router Firmware

Official source article: Cisco CISCO-SA-RV-OSINJ-RCE-PWTKPCJV ↗. Check the applicable product and release in the original source.

4.7MediumCVSS 3.1
Recommended action
Scheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Fix not verified
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityMediumOperational priority:Medium, unchanged from published severity.unchanged

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • EPSS is 2.17% for the current model date.

Compensating controls

  • Restrict the affected network interface to trusted sources where business-safe.
  • Monitor vendor guidance and exploitation sources for a material change.

Verification

  1. Confirm that the asset runs Cisco Cisco Small Business RV Series Router Firmware and falls inside the recorded affected range.
  2. Recheck the vendor advisory before scheduling a change because no verified fixed version is currently retained.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: As exposure requiresRemediation target: Within 365 days

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

Optional official sources

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

Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2020-24722

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionScheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Fix not verified
01

What, why and how

Multiple vulnerabilities in the web-based management interface of Cisco Small Business RV340 Series Routers could allow an authenticated, remote attacker with administrative credentials to execute arbitrary commands on the underlying operating system (OS) as a restricted user. For more information about these vulnerabilities, see the Details section of this advisory.

What

Multiple vulnerabilities in the web-based management interface of Cisco Small Business RV340 Series Routers could allow an authenticated, remote attacker with administrative credentials to execute arbitrary commands on the underlying operating system (OS) as a restricted user. For more information about these vulnerabilities, see the Details section of this advisory.

Why

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.

How

An attacker operating through a network path may attempt exploitation with elevated privileges. If successful, the issue may execute code or commands in the affected security context.

What

Multiple vulnerabilities in the web-based management interface of Cisco Small Business RV340 Series Routers could allow an authenticated, remote attacker with administrative credentials to execute arbitrary commands on the underlying operating system (OS) as a restricted user. For more information about these vulnerabilities, see the Details section of this advisory.

Why

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.

How

An attacker operating through a network path may attempt exploitation with elevated privileges. If successful, the issue may execute code or commands in the affected security context.

02

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
a network path → Improper Restriction of Operations within the Bounds of a Memory Buffer → execute code or commands in the affected security context
Attack surface
Network
Privileges required
High: elevated access is required
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-119 ↗

CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer. The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:L

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRHighPrivileges required: The attacker needs elevated or administrative privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CLowConfidentiality impact: A successful attack can cause a limited loss.ILowIntegrity impact: A successful attack can cause a limited loss.ALowAvailability impact: A successful attack can cause a limited 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.
NetworkRemote code executionCWE-119
A

Official authority intelligence

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

Cyber Security Agency of Singapore · English · CSA-SB-20200909Security Bulletin 09 Sep 2020

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 09 Sep 2020, published on 9 September 2020. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
CERT-FR · French · CERTFR-2020-AVI-580Multiples vulnérabilités dans les routeurs de série RV340 de Cisco

Cet avis fait suite à la mise à jour du bulletin de l'éditeur le 17 septembre. De multiples vulnérabilités ont été découvertes dans les routeurs de série RV340 de Cisco. Elles permettent à un attaquant non-authentifié de provoquer une exécution de code arbitraire à distance via l'interface Web de management de l'équipement avec les droits restreints de l'utilisateur www-data. Par défaut, l'interface de management n'est accessible que depuis le réseau local. Une option permet d'activer cette interface de management sur l'interface WAN pour une prise en main à distance. Pour savoir si l'interface Web de management est activée, depuis le réseau local, il faut se connecter sur cette interface et naviguer dans le menu "Basic Settings > Remote Management" et vérifier si la case "Enable" est cochée.

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2020-010746Cisco Small Business RV340 シリーズルータにおける入力確認に関する脆弱性

Cisco Small Business RV340 シリーズルータには、入力確認に関する脆弱性が存在します。

Official advisory ↗
KISA KrCERT/CC · Korean · KNVD-5203Cisco 제품 취약점 보안 업데이트 권고

#### Cisco 제품 취약점 보안 업데이트 권고 2020.10.05 ##### □ 개요 o Cisco社는 자사 제품의 취약점을 해결한 보안 업데이트 공지 [1] o 공격자는 해당 취약점을 이용하여 원격코드실행 등의 피해를 발생시킬 수 있으므로, 해당 제품을 사용하는 이용자들은 최신 버전으로 업데이트 권고 ##### □ 주요 내용 o Cisco Small Business RV340 Series Routers의 웹 인터페이스에서 입력값 검증이 미흡하여 발생하는 명령어 삽입 및 원격코드실행 취약점(CVE-2020-3451, 3453) [2] o Cisco IOS XE Software에서 권한검증이 미흡하여 발생하는 인증우회 취약점(CVE-2020-3400) [3] o Cisco IOS XE Software에서 특정 HTTP 요청에 대한 검증이 미흡하여 발생하는 권한상승 취약점(CVE-2020-3141) [4] o Cisco IOS XE Software에서 데이터 보호 기능이 미흡하여 발생하는 권한상승 취약점(CVE-2020-3425) [4] o Cisco 800 Series의 IOS Software에서 가상 LPWA 프로토콜 메시지에 대한 검증이 미흡하여 발생하는 정보노출 취약점(CVE-2020-3426) [5] ##### □ 영향 받는 제품 및 해결 방안 o 참고 사이트에 명시되어 있는 Affected Products와 Fixed Software 내용을 참고하여 패치 적용 ##### □ 기타 문의사항 o 한국인터넷진흥원 사이버민원센터: 국번없이 118 [참고사이트] [1] https://tools.cisco.com/security/center/publicationListing.x?product=Cisco&sort=-day_sir#~Vulnerabilities [2] https://tools.cisco.com/security/center/content/Cisco

Official advisory ↗
03

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
Cisco Small Business RV Series Router Firmware: 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. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04

Evidence and provenance

Published 4 Sept 2020 · Last source change 13 Nov 2024, 18:07 UTC · CWE-119 · Improper Restriction of Operations within the Bounds of a Memory Buffer

CVE recordCVE.org · 5.1
CVSS sourceCNA
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-2020-24722
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD modified after enrichment

Core structured fields are present and their contributing authorities are shown above.

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.

Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
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.
Free version - for non-commercial use only.CVE-2020-3451 · cve.blacktree.nl