Cisco IOS XR Software EVPN Operational Routes Denial of Service Vulnerability
Published Jan 26, 2020
6.5
MEDIUMCVSS 3.1
EPSS 1.07%
Description
A vulnerability in the implementation of Border Gateway Protocol (BGP) Ethernet VPN (EVPN) functionality in Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to incorrect processing of a BGP update message that contains crafted EVPN attributes. An attacker could indirectly exploit the vulnerability by sending BGP EVPN update messages with a specific, malformed attribute to an affected system and waiting for a user on the device to display the EVPN operational routes’ status. If successful, the attacker could cause the BGP process to restart unexpectedly, resulting in a DoS condition. The Cisco implementation of BGP accepts incoming BGP traffic only from explicitly defined peers. To exploit this vulnerability, the malicious BGP update message would need to come from a configured, valid BGP peer, or would need to be injected by the attacker into the victim's BGP network on an existing, valid TCP connection to a BGP peer.
Affected products
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- Version unspecifiedStatusaffectedConstraints-
- Version
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||
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| Cisco | Cisco IOS XR Software | n/a |
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Configuration 1
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Configuration 2
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Configuration 3
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Configuration 4
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No data.
No Red Hat product state for this CVE.
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:N/A:H
AV:N/AC:M/Au:N/C:N/I:N/A:P
This CVE is not in the KEV list.
CISA SSVC (Vulnrichment)
Stakeholder-Specific Vulnerability Categorization from CISA ADP.
Exploitation
NoneAutomatable
NoTechnical Impact
PartialDecision
n/aAssessed Nov 15, 2024 · SSVC 2.0.3
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 4, 2026.
Score over time
2021-2026- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
- EPSS v4
Percentile over time
- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
- EPSS v4
Table of values (12 key points)
Flat stretches are collapsed. Showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 4, 2026 | 1.07% (0.01066) | 63.58th | v5 (v2026.06.15) |
| Jun 15, 2026 | 1.07% (0.01066) | 60.25th | v5 (v2026.06.15) |
| May 4, 2025 | 1.72% (0.01718) | 81.36th | v4 (v2025.03.14) |
| Jul 20, 2024 | 0.14% (0.00143) | 50.65th | v3 (v2023.03.01) |
| Jun 20, 2024 | 0.14% (0.00143) | 50.40th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.14% (0.00143) | 48.39th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.05% (0.01055) | 52.13th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.05% (0.01055) | 48.43th | v2 (v2022.01.01) |
| Mar 31, 2022 | 2.56% (0.02561) | 62.63th | v2 (v2022.01.01) |
| Jan 6, 2022 | 2.86% (0.02857) | 63.25th | v1 |
| Jan 5, 2022 | 0.65% (0.00651) | 47.22th | v5 (v2026.06.15) |
| Apr 14, 2021 | 0.65% (0.00651) | 0.00th | v1 |
References (1)
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200122-ios-xr-routes vendor-advisoryx_refsource_CISCOVendor Advisory
| Link | Providers | Tags |
|---|---|---|
| https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200122-ios-xr-routes | vendor-advisoryx_refsource_CISCOVendor Advisory |
Change history (0)
No recorded changes yet.