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TI-2021-01167 Aliases CVE-2021-1440GHSA-g8j6-3mwg-7x4g

Cisco IOS XR Software BGP Resource Public Key Infrastructure Denial of Service Vulnerability

Priority LOW 32CWE-617Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-617.

Summary

A vulnerability in the implementation of the Resource Public Key Infrastructure (RPKI) feature of Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause the Border Gateway Protocol (BGP) process to crash, resulting in a denial of service (DoS) condition. This vulnerability is due to the incorrect handling of a specific RPKI to Router (RTR) Protocol packet header. An attacker could exploit this vulnerability by compromising the RPKI validator server and sending a specifically crafted RTR packet to an affected device. Alternatively, the attacker could use man-in-the-middle techniques to impersonate the RPKI validator server and send a specifically crafted RTR response packet over the established RTR TCP connection to the affected device. A successful exploit could allow the attacker to cause a DoS condition because the BGP process could constantly restart and BGP routing could become unstable.Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.This advisory is part of the September 2021 release of the Cisco IOS XR Software Security Advisory Bundled Publication. For a complete list of the advisories and links to them, see .

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00805 56th 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 XR Software6.6.1; 6.5.3; 7.0.1; 6.6.11; 6.5.1; 6.5.2; 6.6.2; 6.6.12; 6.6.25; 7.1.1; 7.0.90; 6.6.3; 7.0.2; 7.1.2; 7.2.1; 7.0.11; 7.0.12; 7.0.14; 6.6.4; 7.2.12; 7.2.2—No fix listedCNA
  • Cisco IOS XR Software VendorCisco Affected 6.6.1; 6.5.3; 7.0.1; 6.6.11; 6.5.1; 6.5.2; 6.6.2; 6.6.12; 6.6.25; 7.1.1; 7.0.90; 6.6.3; 7.0.2; 7.1.2; 7.2.1; 7.0.11; 7.0.12; 7.0.14; 6.6.4; 7.2.12; 7.2.2 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*4.3.0 to before 7.3.1VulnerableCisco
  • cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:* Versions 4.3.0 to before 7.3.1 Vulnerable ·Cisco

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-1440
  2. 2026-10-03 Alias added: GHSA-g8j6-3mwg-7x4g

References

  • TI-2020-02680 Cisco IOS XR Software Cisco Discovery Protocol Format String Vulnerability KEVCVSS 3.1HIGH 8.8
  • TI-2018-00135 Memory corruption in Cisco IOS, IOS XE, and IOS XR KEVCVSS 3.1HIGH 8.8
  • TI-2020-03113 Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerabilities KEVCVSS 3.1HIGH 8.6
  • TI-2020-03110 Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerability KEVCVSS 3.1HIGH 8.6
  • TI-2018-00142 Memory corruption in Cisco IOS, IOS XE, and IOS XR KEVCVSS 3.1HIGH 8.0
  • TI-2023-23979 The HTTP/2 protocol allows a denial of service (server resource consumption) because… KEVCVSS 3.1HIGH 7.5
See all 199 →

Sources