Vulnerability-Lookup

BDU:2026-17393 (CVE-2026-76505)

Vulnerability from fstec – Published: 2026-10-23 – Updated: 2026-10-23 – View on bdu.fstec.ru Fixed

Title

Уязвимость функции обработки пакетов IPv4 операционной системы Cisco IOS XR сетевых устройств Cisco ASR 9000 и ASR 9900, позволяющая нарушителю вызвать отказ в обслуживании

Summary

Уязвимость функции обработки пакетов IPv4 операционной системы Cisco IOS XR сетевых устройств Cisco ASR 9000 и ASR 9900 связана с недостаточной проверкой входных данных. Эксплуатация уязвимости может позволить нарушителю, действующему удаленно, вызвать отказ в обслуживании

Severity

7.8 (High) CVSS 2.0


                      
                        AV:N/AC:L/Au:N/C:N/I:N/A:C

7.5 (High) CVSS 3.1


                      
                        CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Class

Code vulnerability

Status

Confirmed by the vendor

Exploitation

Resource manipulation

Incidents

Being clarified

Remediation

Software update

CWE

CWE-20 - Недостаточная проверка вводимых данных

Aliases

CVE-2026-76505

References

1 reference

URL
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/c…

Impacted products

1 product from 2 vendors

Vendors

Cisco Systems, Inc.

Products

Cisco IOS XR

Versions

от 24.4 до 24.4.2 (Cisco IOS XR), от 24.2 до 24.2.21 (Cisco IOS XR), до 7.9.2 SMU asr9k-x64-7.9.2.CSCwn39554 (Cisco IOS XR), до 7.9.21 SMU asr9k-x64-7.9.21.CSCwn39554 (Cisco IOS XR), от 7.10 до 7.10.2 SMU asr9k-x64-7.10.2.CSCwn39554 (Cisco IOS XR), от 7.11 до 7.11.2 SMU asr9k-x64-7.11.2.CSCwn39554 (Cisco IOS XR), от 7.11 до 7.11.21 SMU asr9k-x64-7.11.21.CSCwn39554 (Cisco IOS XR), от 24.1 до 24.1.2 SMU asr9k-x64-24.1.2.CSCwn39554 (Cisco IOS XR), от 24.2 до 24.2.2 SMU asr9k-x64-24.2.2.CSCwn39554 (Cisco IOS XR), от 24.3 до 24.3.2 SMU asr9k-x64-24.3.2.CSCwn39554 (Cisco IOS XR)

Product types

Operating system

Platforms

Cisco Systems, Inc. Cisco IOS XR от 24.4 до 24.4.2, Inc. Cisco IOS XR от 24.2 до 24.2.21, Inc. Cisco IOS XR до 7.9.2 SMU asr9k-x64-7.9.2.CSCwn39554, Inc. Cisco IOS XR до 7.9.21 SMU asr9k-x64-7.9.21.CSCwn39554, Inc. Cisco IOS XR от 7.10 до 7.10.2 SMU asr9k-x64-7.10.2.CSCwn39554, Inc. Cisco IOS XR от 7.11 до 7.11.2 SMU asr9k-x64-7.11.2.CSCwn39554, Inc. Cisco IOS XR от 7.11 до 7.11.21 SMU asr9k-x64-7.11.21.CSCwn39554, Inc. Cisco IOS XR от 24.1 до 24.1.2 SMU asr9k-x64-24.1.2.CSCwn39554, Inc. Cisco IOS XR от 24.2 до 24.2.2 SMU asr9k-x64-24.2.2.CSCwn39554, Inc. Cisco IOS XR от 24.3 до 24.3.2 SMU asr9k-x64-24.3.2.CSCwn39554

Mitigations

Использование рекомендаций: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asr9k-tUyxcyXN

JSON

To clipboard

{
  "CVSS 2.0": "AV:N/AC:L/Au:N/C:N/I:N/A:C",
  "CVSS 3.0": "AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
  "CVSS 4.0": null,
  "remediation_\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": null,
  "remediation_\u041d\u0430\u0438\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435": null,
  "\u0412\u0435\u043d\u0434\u043e\u0440 \u041f\u041e": "Cisco Systems, Inc.",
  "\u0412\u0435\u0440\u0441\u0438\u044f \u041f\u041e": "\u043e\u0442 24.4 \u0434\u043e 24.4.2 (Cisco IOS XR), \u043e\u0442 24.2 \u0434\u043e 24.2.21 (Cisco IOS XR), \u0434\u043e 7.9.2 SMU asr9k-x64-7.9.2.CSCwn39554 (Cisco IOS XR), \u0434\u043e 7.9.21 SMU asr9k-x64-7.9.21.CSCwn39554 (Cisco IOS XR), \u043e\u0442 7.10 \u0434\u043e 7.10.2 SMU asr9k-x64-7.10.2.CSCwn39554 (Cisco IOS XR), \u043e\u0442 7.11 \u0434\u043e 7.11.2 SMU asr9k-x64-7.11.2.CSCwn39554 (Cisco IOS XR), \u043e\u0442 7.11 \u0434\u043e 7.11.21 SMU asr9k-x64-7.11.21.CSCwn39554 (Cisco IOS XR), \u043e\u0442 24.1 \u0434\u043e 24.1.2 SMU asr9k-x64-24.1.2.CSCwn39554 (Cisco IOS XR), \u043e\u0442 24.2 \u0434\u043e 24.2.2 SMU asr9k-x64-24.2.2.CSCwn39554 (Cisco IOS XR), \u043e\u0442 24.3 \u0434\u043e 24.3.2 SMU asr9k-x64-24.3.2.CSCwn39554 (Cisco IOS XR)",
  "\u0412\u043e\u0437\u043c\u043e\u0436\u043d\u044b\u0435 \u043c\u0435\u0440\u044b \u043f\u043e \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u044e": "\u0418\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u043d\u0438\u0435 \u0440\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0430\u0446\u0438\u0439:\nhttps://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asr9k-tUyxcyXN",
  "\u0414\u0430\u0442\u0430 \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0438\u044f": "21.10.2026",
  "\u0414\u0430\u0442\u0430 \u043f\u043e\u0441\u043b\u0435\u0434\u043d\u0435\u0433\u043e \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u044f": "23.10.2026",
  "\u0414\u0430\u0442\u0430 \u043f\u0443\u0431\u043b\u0438\u043a\u0430\u0446\u0438\u0438": "23.10.2026",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": "BDU:2026-17393",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440\u044b \u0434\u0440\u0443\u0433\u0438\u0445 \u0441\u0438\u0441\u0442\u0435\u043c \u043e\u043f\u0438\u0441\u0430\u043d\u0438\u0439 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "CVE-2026-76505",
  "\u0418\u043d\u0444\u043e\u0440\u043c\u0430\u0446\u0438\u044f \u043e\u0431 \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0430",
  "\u041a\u043b\u0430\u0441\u0441 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u043a\u043e\u0434\u0430",
  "\u041d\u0430\u0437\u0432\u0430\u043d\u0438\u0435 \u041f\u041e": "Cisco IOS XR",
  "\u041d\u0430\u0438\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435 \u041e\u0421 \u0438 \u0442\u0438\u043f \u0430\u043f\u043f\u0430\u0440\u0430\u0442\u043d\u043e\u0439 \u043f\u043b\u0430\u0442\u0444\u043e\u0440\u043c\u044b": "Cisco Systems, Inc. Cisco IOS XR \u043e\u0442 24.4 \u0434\u043e 24.4.2 , Cisco Systems, Inc. Cisco IOS XR \u043e\u0442 24.2 \u0434\u043e 24.2.21 , Cisco Systems, Inc. Cisco IOS XR \u0434\u043e 7.9.2 SMU asr9k-x64-7.9.2.CSCwn39554 , Cisco Systems, Inc. Cisco IOS XR \u0434\u043e 7.9.21 SMU asr9k-x64-7.9.21.CSCwn39554 , Cisco Systems, Inc. Cisco IOS XR \u043e\u0442 7.10 \u0434\u043e 7.10.2 SMU asr9k-x64-7.10.2.CSCwn39554 , Cisco Systems, Inc. Cisco IOS XR \u043e\u0442 7.11 \u0434\u043e 7.11.2 SMU asr9k-x64-7.11.2.CSCwn39554 , Cisco Systems, Inc. Cisco IOS XR \u043e\u0442 7.11 \u0434\u043e 7.11.21 SMU asr9k-x64-7.11.21.CSCwn39554 , Cisco Systems, Inc. Cisco IOS XR \u043e\u0442 24.1 \u0434\u043e 24.1.2 SMU asr9k-x64-24.1.2.CSCwn39554 , Cisco Systems, Inc. Cisco IOS XR \u043e\u0442 24.2 \u0434\u043e 24.2.2 SMU asr9k-x64-24.2.2.CSCwn39554 , Cisco Systems, Inc. Cisco IOS XR \u043e\u0442 24.3 \u0434\u043e 24.3.2 SMU asr9k-x64-24.3.2.CSCwn39554 ",
  "\u041d\u0430\u0438\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u0444\u0443\u043d\u043a\u0446\u0438\u0438 \u043e\u0431\u0440\u0430\u0431\u043e\u0442\u043a\u0438 \u043f\u0430\u043a\u0435\u0442\u043e\u0432 IPv4 \u043e\u043f\u0435\u0440\u0430\u0446\u0438\u043e\u043d\u043d\u043e\u0439 \u0441\u0438\u0441\u0442\u0435\u043c\u044b Cisco IOS XR \u0441\u0435\u0442\u0435\u0432\u044b\u0445 \u0443\u0441\u0442\u0440\u043e\u0439\u0441\u0442\u0432 Cisco ASR 9000 \u0438 ASR 9900, \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0430\u044f \u043d\u0430\u0440\u0443\u0448\u0438\u0442\u0435\u043b\u044e \u0432\u044b\u0437\u0432\u0430\u0442\u044c \u043e\u0442\u043a\u0430\u0437 \u0432 \u043e\u0431\u0441\u043b\u0443\u0436\u0438\u0432\u0430\u043d\u0438\u0438",
  "\u041d\u0430\u043b\u0438\u0447\u0438\u0435 \u044d\u043a\u0441\u043f\u043b\u043e\u0439\u0442\u0430": "\u0414\u0430\u043d\u043d\u044b\u0435 \u0443\u0442\u043e\u0447\u043d\u044f\u044e\u0442\u0441\u044f",
  "\u041e\u043f\u0438\u0441\u0430\u043d\u0438\u0435 \u043e\u0448\u0438\u0431\u043a\u0438 CWE": "\u041d\u0435\u0434\u043e\u0441\u0442\u0430\u0442\u043e\u0447\u043d\u0430\u044f \u043f\u0440\u043e\u0432\u0435\u0440\u043a\u0430 \u0432\u0432\u043e\u0434\u0438\u043c\u044b\u0445 \u0434\u0430\u043d\u043d\u044b\u0445 (CWE-20)",
  "\u041e\u043f\u0438\u0441\u0430\u043d\u0438\u0435 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u0444\u0443\u043d\u043a\u0446\u0438\u0438 \u043e\u0431\u0440\u0430\u0431\u043e\u0442\u043a\u0438 \u043f\u0430\u043a\u0435\u0442\u043e\u0432 IPv4 \u043e\u043f\u0435\u0440\u0430\u0446\u0438\u043e\u043d\u043d\u043e\u0439 \u0441\u0438\u0441\u0442\u0435\u043c\u044b Cisco IOS XR \u0441\u0435\u0442\u0435\u0432\u044b\u0445 \u0443\u0441\u0442\u0440\u043e\u0439\u0441\u0442\u0432 Cisco ASR 9000 \u0438 ASR 9900 \u0441\u0432\u044f\u0437\u0430\u043d\u0430 \u0441 \u043d\u0435\u0434\u043e\u0441\u0442\u0430\u0442\u043e\u0447\u043d\u043e\u0439 \u043f\u0440\u043e\u0432\u0435\u0440\u043a\u043e\u0439 \u0432\u0445\u043e\u0434\u043d\u044b\u0445 \u0434\u0430\u043d\u043d\u044b\u0445. \u042d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u044f \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438 \u043c\u043e\u0436\u0435\u0442 \u043f\u043e\u0437\u0432\u043e\u043b\u0438\u0442\u044c \u043d\u0430\u0440\u0443\u0448\u0438\u0442\u0435\u043b\u044e, \u0434\u0435\u0439\u0441\u0442\u0432\u0443\u044e\u0449\u0435\u043c\u0443 \u0443\u0434\u0430\u043b\u0435\u043d\u043d\u043e, \u0432\u044b\u0437\u0432\u0430\u0442\u044c \u043e\u0442\u043a\u0430\u0437 \u0432 \u043e\u0431\u0441\u043b\u0443\u0436\u0438\u0432\u0430\u043d\u0438\u0438",
  "\u041f\u043e\u0441\u043b\u0435\u0434\u0441\u0442\u0432\u0438\u044f \u044d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u0438 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": null,
  "\u041f\u0440\u043e\u0447\u0430\u044f \u0438\u043d\u0444\u043e\u0440\u043c\u0430\u0446\u0438\u044f": null,
  "\u0421\u0432\u044f\u0437\u044c \u0441 \u0438\u043d\u0446\u0438\u0434\u0435\u043d\u0442\u0430\u043c\u0438 \u0418\u0411": "\u0414\u0430\u043d\u043d\u044b\u0435 \u0443\u0442\u043e\u0447\u043d\u044f\u044e\u0442\u0441\u044f",
  "\u0421\u043e\u0441\u0442\u043e\u044f\u043d\u0438\u0435 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u041e\u043f\u0443\u0431\u043b\u0438\u043a\u043e\u0432\u0430\u043d\u0430",
  "\u0421\u043f\u043e\u0441\u043e\u0431 \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u044f": "\u041e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u0435 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f",
  "\u0421\u043f\u043e\u0441\u043e\u0431 \u044d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u0438": "\u041c\u0430\u043d\u0438\u043f\u0443\u043b\u0438\u0440\u043e\u0432\u0430\u043d\u0438\u0435 \u0440\u0435\u0441\u0443\u0440\u0441\u0430\u043c\u0438",
  "\u0421\u0441\u044b\u043b\u043a\u0438 \u043d\u0430 \u0438\u0441\u0442\u043e\u0447\u043d\u0438\u043a\u0438": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asr9k-tUyxcyXN",
  "\u0421\u0442\u0430\u0442\u0443\u0441 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u041f\u043e\u0434\u0442\u0432\u0435\u0440\u0436\u0434\u0435\u043d\u0430 \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u0434\u0438\u0442\u0435\u043b\u0435\u043c",
  "\u0422\u0438\u043f \u041f\u041e": "\u041e\u043f\u0435\u0440\u0430\u0446\u0438\u043e\u043d\u043d\u0430\u044f \u0441\u0438\u0441\u0442\u0435\u043c\u0430",
  "\u0422\u0438\u043f \u043e\u0448\u0438\u0431\u043a\u0438 CWE": "CWE-20",
  "\u0423\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0412\u044b\u0441\u043e\u043a\u0438\u0439 \u0443\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 (\u0431\u0430\u0437\u043e\u0432\u0430\u044f \u043e\u0446\u0435\u043d\u043a\u0430 CVSS 2.0 \u0441\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u0442 7,8)\n\u0412\u044b\u0441\u043e\u043a\u0438\u0439 \u0443\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 (\u0431\u0430\u0437\u043e\u0432\u0430\u044f \u043e\u0446\u0435\u043d\u043a\u0430 CVSS 3.1 \u0441\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u0442 7,5)"
}

CVE-2026-76505 (GCVE-0-2026-76505)

Vulnerability from cvelistv5 – Published: 2026-10-21 16:18 – Updated: 2026-10-22 13:37

Title

Cisco IOS XR Software for ASR 9000 Series Routers IPv4 Unicast Packets Denial of Service Vulnerability

Summary

A vulnerability in the IPv4 packet processing functionality of Cisco IOS XR Software that affects Cisco ASR 9000 and 9900 Series Aggregation Services Routers as well as Cisco ASR 9902 and 9903 Compact High-Performance Routers could allow an unauthenticated, remote attacker to cause network processor (NP) errors, resulting in a line card reset or shutdown and a denial of service (DoS) condition. This vulnerability is due to the incorrect handling of crafted IPv4 packets that are received on an affected line card interface and processed as for-us traffic. The issue can result in an NP reset, causing traffic loss on the affected line card while it recovers. Under repeated reset conditions, the network processor may enter a persistent shutdown state, in which case an explicit line card reload may be required to restore traffic. The vulnerability is within the IPv4 packet-processing path. Transit IPv4 traffic does not trigger this issue and IPv6 traffic cannot trigger it.

Severity

7.5 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-10-21 17:11 UTC

CWE

CWE-20 - Improper Input Validation

Assigner

cisco CNA under the mitre root

CNA scorecard C 66/100 over 443 records in the last 180 days details

References

1 reference

URL	Tags
https://sec.cloudapps.cisco.com/security/center/c…

Impacted products

1 product

Vendor	Product	Version
Cisco	Cisco IOS XR Software	Affected: 7.0.1 Affected: 7.1.1 Affected: 7.0.90 Affected: 6.7.1 Affected: 7.0.2 Affected: 7.1.15 Affected: 7.1.2 Affected: 6.7.2 Affected: 7.1.25 Affected: 7.1.3 Affected: 6.7.3 Affected: 7.3.1 Affected: 7.4.1 Affected: 6.8.1 Affected: 7.3.2 Affected: 7.5.1 Affected: 7.6.1 Affected: 7.5.2 Affected: 7.3.3 Affected: 6.8.2 Affected: 7.7.1 Affected: 7.4.2 Affected: 7.3.4 Affected: 6.7.35 Affected: 6.9.1 Affected: 7.6.2 Affected: 7.8.1 Affected: 7.5.3 Affected: 7.7.2 Affected: 6.9.2 Affected: 7.9.1 Affected: 7.8.2 Affected: 7.5.4 Affected: 7.8.22 Affected: 7.10.1 Affected: 7.9.2 Affected: 7.3.5 Affected: 7.5.5 Affected: 7.11.1 Affected: 7.9.21 Affected: 7.10.2 Affected: 24.1.1 Affected: 7.11.2 Affected: 24.2.1 Affected: 24.1.2 Affected: 24.3.1 Affected: 24.4.1 Affected: 24.2.2 Affected: 7.8.23 Affected: 7.11.21 Affected: 24.3.2 Affected: 24.3.20 Affected: 24.3.30

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{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-76505",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-10-21T17:11:38.778800Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
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        ],
        "providerMetadata": {
          "dateUpdated": "2026-10-22T13:37:51.885Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
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              "version": "7.0.1"
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              "version": "7.4.1"
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              "status": "affected",
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              "status": "affected",
              "version": "7.3.2"
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              "status": "affected",
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            {
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            {
              "status": "affected",
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            },
            {
              "status": "affected",
              "version": "7.4.2"
            },
            {
              "status": "affected",
              "version": "7.3.4"
            },
            {
              "status": "affected",
              "version": "6.7.35"
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            {
              "status": "affected",
              "version": "6.9.1"
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            {
              "status": "affected",
              "version": "7.6.2"
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            {
              "status": "affected",
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              "status": "affected",
              "version": "7.5.3"
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              "status": "affected",
              "version": "7.7.2"
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              "status": "affected",
              "version": "6.9.2"
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            {
              "status": "affected",
              "version": "7.9.1"
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            {
              "status": "affected",
              "version": "7.8.2"
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            {
              "status": "affected",
              "version": "7.5.4"
            },
            {
              "status": "affected",
              "version": "7.8.22"
            },
            {
              "status": "affected",
              "version": "7.10.1"
            },
            {
              "status": "affected",
              "version": "7.9.2"
            },
            {
              "status": "affected",
              "version": "7.3.5"
            },
            {
              "status": "affected",
              "version": "7.5.5"
            },
            {
              "status": "affected",
              "version": "7.11.1"
            },
            {
              "status": "affected",
              "version": "7.9.21"
            },
            {
              "status": "affected",
              "version": "7.10.2"
            },
            {
              "status": "affected",
              "version": "24.1.1"
            },
            {
              "status": "affected",
              "version": "7.11.2"
            },
            {
              "status": "affected",
              "version": "24.2.1"
            },
            {
              "status": "affected",
              "version": "24.1.2"
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            {
              "status": "affected",
              "version": "24.3.1"
            },
            {
              "status": "affected",
              "version": "24.4.1"
            },
            {
              "status": "affected",
              "version": "24.2.2"
            },
            {
              "status": "affected",
              "version": "7.8.23"
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            {
              "status": "affected",
              "version": "7.11.21"
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            {
              "status": "affected",
              "version": "24.3.2"
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              "status": "affected",
              "version": "24.3.20"
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        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "A vulnerability in the IPv4 packet processing functionality of Cisco IOS XR Software that affects Cisco ASR 9000 and 9900 Series Aggregation Services Routers as well as Cisco ASR 9902 and 9903 Compact High-Performance Routers could allow an unauthenticated, remote attacker to cause network processor (NP) errors, resulting in a line card reset or shutdown and a denial of service (DoS) condition.\u0026nbsp;\r\n\r\nThis vulnerability is due to the incorrect handling of crafted IPv4 packets that are received on an affected line card interface and processed as for-us traffic. The issue can result in an NP reset, causing traffic loss on the affected line card while it recovers. Under repeated reset conditions, the network processor may enter a persistent shutdown state, in which case an explicit line card reload may be required to restore traffic.\r\nThe vulnerability is within the IPv4 packet-processing path. Transit IPv4 traffic does not trigger this issue and IPv6 traffic cannot trigger it."
        }
      ],
      "exploits": [
        {
          "lang": "en",
          "value": "The Cisco PSIRT is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          },
          "format": "cvssV3_1"
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      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-20",
              "description": "Improper Input Validation",
              "lang": "en",
              "type": "cwe"
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          ]
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      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-21T16:18:12.195Z",
        "orgId": "d1c1063e-7a18-46af-9102-31f8928bc633",
        "shortName": "cisco"
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      "references": [
        {
          "name": "cisco-sa-asr9k-tUyxcyXN",
          "url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asr9k-tUyxcyXN"
        }
      ],
      "source": {
        "advisory": "cisco-sa-asr9k-tUyxcyXN",
        "defects": [
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        "discovery": "INTERNAL"
      },
      "title": "Cisco IOS XR Software for ASR 9000 Series Routers IPv4 Unicast Packets Denial of Service Vulnerability"
    }
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  "cveMetadata": {
    "assignerOrgId": "d1c1063e-7a18-46af-9102-31f8928bc633",
    "assignerShortName": "cisco",
    "cveId": "CVE-2026-76505",
    "datePublished": "2026-10-21T16:18:12.195Z",
    "dateReserved": "2026-08-19T12:02:03.641Z",
    "dateUpdated": "2026-10-22T13:37:51.885Z",
    "state": "PUBLISHED"
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}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

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