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TI-2020-03025 Aliases CVE-2020-3479GHSA-2x7q-2hq7-j42j

Cisco IOS and IOS XE Software MP-BGP EVPN Denial of Service Vulnerability

Priority LOW 35CWE-20Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-400.

Summary

A vulnerability in the implementation of Multiprotocol Border Gateway Protocol (MP-BGP) for the Layer 2 VPN (L2VPN) Ethernet VPN (EVPN) address family in Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to incorrect processing of Border Gateway Protocol (BGP) update messages that contain crafted EVPN attributes. An attacker could exploit this vulnerability by sending BGP update messages with specific, malformed attributes to an affected device. A successful exploit could allow the attacker to cause an affected device to crash, resulting in a DoS condition.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01097 65th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
CiscoCisco IOS 15.2(5)E1all versions—No fix listedCNA
  • Cisco IOS 15.2(5)E1 VendorCisco Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 26

CPEVersionsRoleVendor
cpe:2.3:o:cisco:ios:-:*:*:*:*:*:*:*not specified by NVDVulnerableCisco
cpe:2.3:o:cisco:ios_xe:-:*:*:*:*:*:*:*not specified by NVDVulnerableCisco
cpe:2.3:h:cisco:1100_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:1101_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:1109_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:1111x_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:111x_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:1120_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:1160_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:4221_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
  • cpe:2.3:o:cisco:ios:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Cisco
  • cpe:2.3:o:cisco:ios_xe:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Cisco
  • cpe:2.3:h:cisco:1100_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:1101_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:1109_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:1111x_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:111x_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:1120_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:1160_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:4221_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
Show 16 more CPE
CPEVersionsRoleVendor
cpe:2.3:h:cisco:4321_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:4331_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:4351_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:4431_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:4451-x_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:4461_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:asr_1001-hx:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:asr_1001-x:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:asr_1002-hx:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:asr_1002-x:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:asr_1004:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:asr_1006:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:asr_1006-x:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:asr_1009-x:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:asr_1013:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:cloud_services_router_1000v:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
  • cpe:2.3:h:cisco:4321_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:4331_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:4351_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:4431_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:4451-x_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:4461_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:asr_1001-hx:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:asr_1001-x:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:asr_1002-hx:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:asr_1002-x:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:asr_1004:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:asr_1006:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:asr_1006-x:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:asr_1009-x:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:asr_1013:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:cloud_services_router_1000v:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2020-3479
  2. 2026-10-03 Alias added: GHSA-2x7q-2hq7-j42j

References

Advisory 1

  • TI-2018-00138 Improper input validation in Cisco IOS and IOS XE KEVCVSS 3.1CRITICAL 9.8
  • TI-2017-09019 Improper input validation in Cisco IOS and IOS XE KEVCVSS 3.1CRITICAL 9.8
  • TI-2017-02977 Improper input validation in Cisco IOS and IOS XE Software KEVCVSS 3.1CRITICAL 9.8
  • TI-2018-00135 Memory corruption in Cisco IOS, IOS XE, and IOS XR KEVCVSS 3.1HIGH 8.8
  • TI-2017-04499 Memory corruption in Cisco IOS KEVCVSS 3.1HIGH 8.8
  • TI-2017-04498 Memory corruption in Cisco IOS KEVCVSS 3.1HIGH 8.8
See all 617 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences