Cyber Resilience

CVE-2021-1472

Auth Bypass in Cisco Rv160 Firmware ≤ 1.0.01.03

Public PoCHigh EPSSAuth BypassMemory Safety
Published
08 April 2021
Modified
21 November 2024
Patch / advisory
CVSS Score v3.1 5.3
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
EPSS Score 0.72 99.4th percentile
Risk Priority 80 floored blend · peak EPSS

Summary

CVE-2021-1472 is a medium-severity Improper Restriction of Operations within the Bounds of a Memory Buffer (CWE-119) vulnerability in Cisco Rv160 Firmware. Its CVSS base score is 5.3 (Medium).

Operationally, ranked in the top 0.6% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Multiple vulnerabilities exist in the web-based management interface of Cisco Small Business RV Series Routers. A remote attacker could execute arbitrary commands or bypass authentication and upload files on an affected device. For more information about these vulnerabilities, see the…

more

Details section of this advisory.

CWE(s)

Related Threats

Likely ATT&CK TechniquesAI

Techniques this vulnerability likely enables, inferred from its description, weakness type, and attributed-actor tradecraft. Confidence is per-technique.

T1190 Exploit Public-Facing Application Initial Accessconfidence: HIGH
Remote command execution and authentication bypass in the web management interface directly enables exploitation of a public-facing network device.
T1505.003 Web Shell Persistenceconfidence: MEDIUM
File upload capability after bypassing authentication can be used to place a web shell on the router.
T1059 Command and Scripting Interpreter Executionconfidence: MEDIUM
Arbitrary command execution on the device allows use of the command-line interpreter present on the router OS.
inferred from description + CWE · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2021-1473Same product: Cisco Rv340
CVE-2017-6738Same vendor: Cisco
CVE-2017-6737Same vendor: Cisco
CVE-2017-6736Same vendor: Cisco
CVE-2017-6742Same vendor: Cisco
CVE-2018-0151Same vendor: Cisco
CVE-2023-20238Same vendor: Cisco
CVE-2026-20182Same vendor: Cisco
CVE-2026-20127Same vendor: Cisco
CVE-2017-6743Same vendor: Cisco

Affected Assets

cisco
rv160 firmware
≤ 1.0.01.03
cisco
rv160w firmware
≤ 1.0.01.03
cisco
rv260 firmware
≤ 1.0.01.03
cisco
rv260p firmware
≤ 1.0.01.03
cisco
rv260w firmware
≤ 1.0.01.03
cisco
rv340 firmware
≤ 1.0.03.21
cisco
rv340w firmware
≤ 1.0.03.21
cisco
rv345 firmware
≤ 1.0.03.21
cisco
rv345p firmware
≤ 1.0.03.21

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 8 hardening rules · 5 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V17.3.2
  • V6.4.4
  • V6.5.4
  • V6.5.5

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-119 CWE-287

Ongoing control assessments and code testing (static/dynamic analysis, fuzzing) surface memory buffer restriction failures, which are then remediated before release.

addresses: CWE-287 CWE-119

Detects unauthorized use and connections stemming from authentication bypass or failure.

addresses: CWE-287

Detects unauthorized successful logons resulting from improper authentication implementations.

addresses: CWE-287

Documented procedures ensure personnel are trained on authentication mechanisms, tangibly lowering the risk of improper authentication being exploited.

addresses: CWE-287

Security awareness training instructs users on secure authentication practices and avoiding credential compromise.

addresses: CWE-287

Training on authentication mechanisms and best practices decreases the occurrence of improper authentication.

addresses: CWE-287

Non-repudiation requires strong authentication mechanisms to irrefutably attribute performed actions to specific individuals or processes.

addresses: CWE-287

Session content review can reveal authentication bypasses or failures in session establishment.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.AA-03 mostly match
prevents

PR.AA-03 directly enforces authentication mechanisms that eliminate most improper-authentication defects, yet CWE-287 spans additional vectors (missing checks, flawed protocols, session handling) that one control does not fully close.

PR.AA-04 mostly match
prevents

PR.AA-04 directly enables verification of identity assertions (mostly preventing CWE-287 in that scope) yet leaves many other authentication failure modes unaddressed (only partial prevention overall).

PR.PS-06 mostly match
prevents

Secure SDLC practices (bounds checking, safe APIs, reviews) directly prevent this class of flaw.

ID.RA-01 partial match
prevents

Vulnerability scanning and code analysis directly surface buffer-boundary flaws.

ID.RA-08 partial match
prevents

Receiving and triaging vulnerability disclosures commonly includes buffer-related reports.

PR.AA-01 partial match
prevents

PR.AA-01 supplies and governs credentials/tokens that authentication relies on, removing some weak-credential cases, yet leaves verification logic, missing checks, and protocol flaws untouched.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

prevents

Requiring authentication methods whose strength matches the sensitivity of the data and mandating multi-factor authentication directly blocks attempts to access resources without proving identity.

prevents

Verifying user identity before issuing replacement credentials and forcing changes after compromise reduces the likelihood that authentication bypass can be achieved through stolen or weak credentials.

detects

Security testing in development catches out-of-bounds accesses before release, covering most instances of the weakness.

prevents

Mandating segregated approval and oversight for non-human identities reduces the chance that weak or orphaned credentials can be exploited for unauthorized authentication.

mitigates

Requiring authentication mechanisms and technical parameters for secure connections ensures that network services verify user identity before granting access, preventing exploitation of missing or weak authentication.

prevents

Secure development lifecycle mandates memory-safety practices that directly prevent buffer-boundary violations.

References