CVE-2019-1849
mediumpriority · track · 26EPSS 0.006 · 51 %ileEURUUSEPSS · scored 2026-10-27
A vulnerability in the Border Gateway Patrol (BGP) Multiprotocol Label Switching (MPLS)-based Ethernet VPN (EVPN) implementation of Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to trigger a denial of service (DoS) condition on an affected device. The vulnerability is due to a logic error that occurs when the affected software processes specific EVPN routing information. An attacker could exploit this vulnerability by injecting malicious traffic patterns into the targeted EVPN network. A successful exploit could result in a crash of the l2vpn_mgr process on Provider Edge (PE) device members of the same EVPN instance (EVI). On each of the affected devices, a crash could lead to system instability and the inability to process or forward traffic through the device, resulting in a DoS condition that would require manual intervention to restore normal operating conditions.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- FixedCisco IOS XR Softwarecisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6–7.4
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (12)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- cisco-sa-20190515-iosxr-evpn-dosCisco IOS XR Software BGP MPLS-Based EVPN Denial of Service Vulnerability2019-05-15csaf · cisco_csafUS
A vulnerability in the Border Gateway Protocol (BGP) Multiprotocol Label Switching (MPLS)-based Ethernet VPN (EVPN) implementation of Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to trigger a denial of service (DoS) condition on an affected device. The vulnerability is due to a logic error that occurs when the affected software processes specific EVPN routing information. An attacker could exploit this vulnerability by injecting malicious traffic patterns into the targeted EVPN network. A successful exploit could result in a crash of the l2vpn_mgr process on Provider Edge (PE) device members of the same EVPN instance (EVI). On each of the affected devices, a crash could lead to system instability and the inability to process or forward traffic through the device, resulting in a DoS condition that would require manual intervention to restore normal operating conditions. Cisco has released software updates that address this vulnerability. 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-20190515-iosxr-evpn-dos ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190515-iosxr-evpn-dos"]
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (14)
External citations — patches, advisories, analysis.
- http://www.cisco.com/cnnvd
- http://www.securityfocus.com/bid/108342cnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2019-1849cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190515-iosxr-evpn-doscnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190515-iosxr-mpls-doscnnvd
- https://vigilance.fr/vulnerability/Cisco-IOS-XR-denial-of-service-via-MPLS-29319cnnvd
- https://www.auscert.org.au/bulletins/81202cnnvd
- https://www.auscert.org.au/bulletins/ESB-2019.1779.2/cnnvd
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