CVE-2020-3496

mediumpriority · track · 22EPSS 0.017 · 78 %ileEURUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
1.74% (78th) EPSS
CVSS 5 · medium
Is it mine?
123 products
Check your exposure
Who says so?
5 sources
cnnvd · enisa_euvd · fstec_bdu · cisco_csaf

EPSS · scored 2026-10-27

A vulnerability in the IPv6 packet processing engine of Cisco Small Business Smart and Managed Switches could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to insufficient validation of incoming IPv6 traffic. An attacker could exploit this vulnerability by sending a crafted IPv6 packet through an affected device. A successful exploit could allow the attacker to cause the switch management CLI to stop responding, resulting in a DoS condition. This vulnerability is specific to IPv6 traffic. IPv4 traffic is not affected.

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

02

cvss

Technical severity, 0–10. One row per scoring source.

5.3
010

base score 0–10 · higher = more severe · hover a vector to decode

v2.05mediumAV:N/AC:L/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 10 · impact 2.9
v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Lprimary · NVD / NIST USexploitability 3.9 · impact 1.4
v3.05.3mediumCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Lsecondary · ENISA EU
v3.05.3mediumCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Lsecondary · psirt@cisco.com USexploitability 3.9 · impact 1.4
v3.05.3mediumCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Lsecondary · Cisco PSIRT US
v3.15.3mediumAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Lsecondary · FSTEC (BDU) RU
v3.14.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:Usecondary · CVSS-BT (t0sche)
03

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-20USprimaryCWE-20US
05

affected products (123)

Products and version ranges known to be affected.

showing 20 of 123
06

advisories (1)

Vendor and ecosystem advisories describing this.

  • cisco-sa-sbss-ipv6-dos-tsgqbffWCisco Small Business Smart and Managed Switches Denial of Service Vulnerability2020-08-19csaf · cisco_csafUS

    A vulnerability in the IPv6 packet processing engine of Cisco Small Business Smart and Managed Switches could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to insufficient validation of incoming IPv6 traffic. An attacker could exploit this vulnerability by sending a crafted IPv6 packet through an affected device. A successful exploit could allow the attacker to cause the switch management CLI to stop responding, resulting in a DoS condition. This vulnerability is specific to IPv6 traffic. IPv4 traffic is not affected. There are no workarounds that address this vulnerability. This advisory is available at the following link: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sbss-ipv6-dos-tsgqbffW ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sbss-ipv6-dos-tsgqbffW"]

07

also known as (4)

Other names and identifiers for this entity.

08

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bducisco_csafnvdNVDCVE.orgMITRE
published 2020-08-26modified 2026-06-17
10

references (6)

External citations — patches, advisories, analysis.

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