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CVE-2023-20109

Cisco IOS and IOS XE Group Encrypted Transport VPN Out-of-Bounds Write Vulnerability

Published Sep 27, 2023 · updated Jun 16, 2026 · cisco ios

A vulnerability in the Cisco Group Encrypted Transport VPN (GET VPN) feature of Cisco IOS Software and Cisco IOS XE Software could allow an authenticated, remote attacker who has administrative control of either a group member or a key server to execute arbitrary code on an affected device or cause the device to crash. This vulnerability is due to insufficient validation of attributes in the Group Domain of Interpretation (GDOI) and G-IKEv2 protocols of the GET VPN feature. An attacker could exploit this vulnerability by either compromising an installed key server or modifying the configuration of a group member to point to a key server that is controlled by the attacker. A successful exploit could allow the attacker to execute arbitrary code and gain full control of the affected system or cause the affected system to reload, resulting in a denial of service (DoS) condition. For more information, see the Details ["#details"] section of this advisory.

Timeline

Detection, updates, and resolution for this record.

  1. Sep 27, 2023 · Catalog

    Detected

    A vulnerability in the Cisco Group Encrypted Transport VPN (GET VPN) feature of Cisco IOS Software and Cisco IOS XE Software could allow an authenticated, remote attacker who has administrative control of either a group member or a key server to execute arbitrary code on an affected device or cause the device to crash. This vulnerability is due to insufficient validation of attributes in the Group

  2. Oct 10, 2023 · CISA KEV

    Known exploited

    Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

  3. Oct 31, 2023 · CISA KEV

    Remediation due

    Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

  4. Jun 16, 2026 · Catalog

    Updated

    A vulnerability in the Cisco Group Encrypted Transport VPN (GET VPN) feature of Cisco IOS Software and Cisco IOS XE Software could allow an authenticated, remote attacker who has administrative control of either a group member or a key server to execute arbitrary code on an affected device or cause the device to crash. This vulnerability is due to insufficient validation of attributes in the Group

Required action

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

CISA due date Oct 31, 2023

Affected

  • cpe cisco/ios12.4\(22\)md
  • cpe cisco/ios12.4\(22\)md1
  • cpe cisco/ios12.4\(22\)md2
  • cpe cisco/ios12.4\(22\)mda
  • cpe cisco/ios12.4\(22\)mda1
  • cpe cisco/ios12.4\(22\)mda2
  • cpe cisco/ios12.4\(22\)mda3
  • cpe cisco/ios12.4\(22\)mda4
  • cpe cisco/ios xe3.3.0sg
  • vendor Cisco IOS and IOS XEversion unspecified

Sources

  • CISA KEVCVE-2023-20109

    Cisco IOS and IOS XE contain an out-of-bounds write vulnerability in the Group Encrypted Transport VPN (GET VPN) feature that could allow an authenticated, remote attacker who has administrative control of either a group member or a key server to execute malicious code or cause a device to crash.

    cisa.gov
  • CVE.orgCVE-2023-20109

    Official CVE identifier

    cve.org
  • FIRST EPSSCVE-2023-20109

    30-day exploitation probability 2.5%

    first.org
  • NIST NVDCVE-2023-20109

    A vulnerability in the Cisco Group Encrypted Transport VPN (GET VPN) feature of Cisco IOS Software and Cisco IOS XE Software could allow an authenticated, remote attacker who has administrative control of either a group member or a key server to execute arbitrary code on an affec

    nvd.nist.gov

References