CVE-2021-1308 | Cisco Small Business RV Series Routers Link Layer Discovery Protocol Vulnerabilities

Multiple vulnerabilities exist in the Link Layer Discovery Protocol (LLDP) implementation for Cisco Small Business RV Series Routers. An unauthenticated, adjacent attacker could execute arbitrary code or cause an affected router to leak system memory or reload. A memory leak or device reload would cause a denial of service (DoS) condition on an affected device. For more information about these vulnerabilities, see the Details section of this advisory. Note: LLDP is a Layer 2 protocol. To exploit these vulnerabilities, an attacker must be in the same broadcast domain as the affected device (Layer 2 adjacent).

Published: 2021-04-08 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2021-1308 is rated Moderate Risk (42/100): CVSS High severity, with low exploitation likelihood (EPSS 0.43%). Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-1308

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.05% 0.43% +0.38%
2 2023-03-07 1.04% 0.05% -0.98%
3 2022-04-01 1.04%

Full EPSS history (6 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-1308

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.4 3.1 HIGH
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H Click to expand
Attack vector (AV:A)
Attacker has to be nearby on the network—same office, same link, that vibe—not the whole wide internet.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
2.8 4.0 [email protected]
7.4 3.1 HIGH
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H Click to expand
Attack vector (AV:A)
Attacker has to be nearby on the network—same office, same link, that vibe—not the whole wide internet.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
2.8 4.0 [email protected]
6.1 2.0 MEDIUM
AV:A/AC:L/Au:N/C:N/I:N/A:C Click to expand
Access vector (AV:A)
Requires access to an adjacent network segment.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:C)
Complete availability impact.
6.5 6.9 [email protected]

Weakness enumeration for CVE-2021-1308

Affected software / configurations for CVE-2021-1308

Vendor Product Version Raw CPE
cisco rv132w_firmware 1.0.0.14 cpe:2.3:o:cisco:rv132w_firmware:1.0.0.14:*:*:*:*:*:*:*
cisco rv132w_firmware 1.0.1.14 cpe:2.3:o:cisco:rv132w_firmware:1.0.1.14:*:*:*:*:*:*:*
cisco rv132w_firmware 1.0.1.20 cpe:2.3:o:cisco:rv132w_firmware:1.0.1.20:*:*:*:*:*:*:*
cisco rv134w_firmware 1.0.0.14 cpe:2.3:o:cisco:rv134w_firmware:1.0.0.14:*:*:*:*:*:*:*
cisco rv134w_firmware 1.0.1.14 cpe:2.3:o:cisco:rv134w_firmware:1.0.1.14:*:*:*:*:*:*:*
cisco rv134w_firmware 1.0.1.20 cpe:2.3:o:cisco:rv134w_firmware:1.0.1.20:*:*:*:*:*:*:*
cisco rv160_firmware 1.0.0.14 cpe:2.3:o:cisco:rv160_firmware:1.0.0.14:*:*:*:*:*:*:*
cisco rv160_firmware 1.0.1.14 cpe:2.3:o:cisco:rv160_firmware:1.0.1.14:*:*:*:*:*:*:*
cisco rv160_firmware 1.0.1.20 cpe:2.3:o:cisco:rv160_firmware:1.0.1.20:*:*:*:*:*:*:*
cisco rv160w_firmware 1.0.0.14 cpe:2.3:o:cisco:rv160w_firmware:1.0.0.14:*:*:*:*:*:*:*
cisco rv160w_firmware 1.0.1.14 cpe:2.3:o:cisco:rv160w_firmware:1.0.1.14:*:*:*:*:*:*:*
cisco rv160w_firmware 1.0.1.20 cpe:2.3:o:cisco:rv160w_firmware:1.0.1.20:*:*:*:*:*:*:*
cisco rv260_firmware 1.0.0.14 cpe:2.3:o:cisco:rv260_firmware:1.0.0.14:*:*:*:*:*:*:*
cisco rv260_firmware 1.0.1.14 cpe:2.3:o:cisco:rv260_firmware:1.0.1.14:*:*:*:*:*:*:*
cisco rv260_firmware 1.0.1.20 cpe:2.3:o:cisco:rv260_firmware:1.0.1.20:*:*:*:*:*:*:*
cisco rv260p_firmware 1.0.0.14 cpe:2.3:o:cisco:rv260p_firmware:1.0.0.14:*:*:*:*:*:*:*
cisco rv260p_firmware 1.0.1.14 cpe:2.3:o:cisco:rv260p_firmware:1.0.1.14:*:*:*:*:*:*:*
cisco rv260p_firmware 1.0.1.20 cpe:2.3:o:cisco:rv260p_firmware:1.0.1.20:*:*:*:*:*:*:*
cisco rv260w_firmware 1.0.0.14 cpe:2.3:o:cisco:rv260w_firmware:1.0.0.14:*:*:*:*:*:*:*
cisco rv260w_firmware 1.0.1.14 cpe:2.3:o:cisco:rv260w_firmware:1.0.1.14:*:*:*:*:*:*:*
cisco rv260w_firmware 1.0.1.20 cpe:2.3:o:cisco:rv260w_firmware:1.0.1.20:*:*:*:*:*:*:*
cisco rv340_firmware 1.0.0.14 cpe:2.3:o:cisco:rv340_firmware:1.0.0.14:*:*:*:*:*:*:*
cisco rv340_firmware 1.0.1.14 cpe:2.3:o:cisco:rv340_firmware:1.0.1.14:*:*:*:*:*:*:*
cisco rv340_firmware 1.0.1.20 cpe:2.3:o:cisco:rv340_firmware:1.0.1.20:*:*:*:*:*:*:*
cisco rv340w_firmware 1.0.0.14 cpe:2.3:o:cisco:rv340w_firmware:1.0.0.14:*:*:*:*:*:*:*
cisco rv340w_firmware 1.0.1.14 cpe:2.3:o:cisco:rv340w_firmware:1.0.1.14:*:*:*:*:*:*:*
cisco rv340w_firmware 1.0.1.20 cpe:2.3:o:cisco:rv340w_firmware:1.0.1.20:*:*:*:*:*:*:*
cisco rv345_firmware 1.0.0.14 cpe:2.3:o:cisco:rv345_firmware:1.0.0.14:*:*:*:*:*:*:*
cisco rv345_firmware 1.0.1.14 cpe:2.3:o:cisco:rv345_firmware:1.0.1.14:*:*:*:*:*:*:*
cisco rv345_firmware 1.0.1.20 cpe:2.3:o:cisco:rv345_firmware:1.0.1.20:*:*:*:*:*:*:*
cisco rv345p_firmware 1.0.0.14 cpe:2.3:o:cisco:rv345p_firmware:1.0.0.14:*:*:*:*:*:*:*
cisco rv345p_firmware 1.0.1.14 cpe:2.3:o:cisco:rv345p_firmware:1.0.1.14:*:*:*:*:*:*:*
cisco rv345p_firmware 1.0.1.20 cpe:2.3:o:cisco:rv345p_firmware:1.0.1.20:*:*:*:*:*:*:*

References for CVE-2021-1308

cvelogic Threat Intelligence