Cisco IOS XE Software SNMP Denial of Service Vulnerability

Summary

CVECVE-2026-20124
StatePUBLISHED
Assignercisco
Source PriorityCVE Program / NVD first with legacy fallback
Published2026-08-05 17:16:46 UTC
Updated2026-08-06 15:44:56 UTC
DescriptionA vulnerability in the Simple Network Management Protocol (SNMP) subsystem of Cisco IOS XE Software could allow an authenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. This vulnerability is due to improper error handling when parsing SNMP requests. This vulnerability affects all versions of SNMP — Versions 1, 2c, and 3. An attacker could exploit this vulnerability by sending a malformed SNMP request to an affected device. A successful exploit could allow the attacker to cause the device to reload unexpectedly. The attacker must have the SNMPv1 or v2c read-only or read-write community string or valid SNMPv3 user credentials on the affected device.

Risk And Classification

Primary CVSS: v3.1 7.7 HIGH from [email protected]

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

EPSS: 0.003450000 probability, percentile 0.271640000 (date 2026-08-09)

Problem Types: CWE-772 | CWE-772 Missing Release of Resource after Effective Lifetime


VersionSourceTypeScoreSeverityVector
3.1[email protected]Secondary7.7HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H
3.1CNACVSSV3_17.7HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H

CVSS v3.1 Breakdown

Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Changed
Confidentiality
None
Integrity
None
Availability
High

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

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA Cisco Cisco IOS XE Software affected 17.2.1a Not specified
CNA Cisco Cisco IOS XE Software affected 3.18.7SP Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.1y Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.3s Not specified
CNA Cisco Cisco IOS XE Software affected 16.7.1b Not specified
CNA Cisco Cisco IOS XE Software affected 16.6.2 Not specified
CNA Cisco Cisco IOS XE Software affected 16.6.5 Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.1w Not specified
CNA Cisco Cisco IOS XE Software affected 3.18.4S Not specified
CNA Cisco Cisco IOS XE Software affected 16.9.1d Not specified
CNA Cisco Cisco IOS XE Software affected 17.3.1 Not specified
CNA Cisco Cisco IOS XE Software affected 16.9.4c Not specified
CNA Cisco Cisco IOS XE Software affected 16.7.1 Not specified
CNA Cisco Cisco IOS XE Software affected 17.2.1 Not specified
CNA Cisco Cisco IOS XE Software affected 16.6.8 Not specified
CNA Cisco Cisco IOS XE Software affected 16.9.1b Not specified
CNA Cisco Cisco IOS XE Software affected 3.16.8S Not specified
CNA Cisco Cisco IOS XE Software affected 16.9.2s Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.4 Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.3a Not specified
CNA Cisco Cisco IOS XE Software affected 17.1.1s Not specified
CNA Cisco Cisco IOS XE Software affected 16.11.1a Not specified
CNA Cisco Cisco IOS XE Software affected 16.7.2 Not specified
CNA Cisco Cisco IOS XE Software affected 16.11.1b Not specified
CNA Cisco Cisco IOS XE Software affected 16.9.1s Not specified
CNA Cisco Cisco IOS XE Software affected 16.9.3h Not specified
CNA Cisco Cisco IOS XE Software affected 16.9.1c Not specified
CNA Cisco Cisco IOS XE Software affected 16.6.5a Not specified
CNA Cisco Cisco IOS XE Software affected 16.6.3 Not specified
CNA Cisco Cisco IOS XE Software affected 16.10.1f Not specified
CNA Cisco Cisco IOS XE Software affected 17.2.1v Not specified
CNA Cisco Cisco IOS XE Software affected 16.8.1e Not specified
CNA Cisco Cisco IOS XE Software affected 16.9.3a Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.1a Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.1x Not specified
CNA Cisco Cisco IOS XE Software affected 3.16.10aS Not specified
CNA Cisco Cisco IOS XE Software affected 16.6.4s Not specified
CNA Cisco Cisco IOS XE Software affected 16.10.1c Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.3 Not specified
CNA Cisco Cisco IOS XE Software affected 16.11.2 Not specified
CNA Cisco Cisco IOS XE Software affected 16.6.5b Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.2s Not specified
CNA Cisco Cisco IOS XE Software affected 16.10.1b Not specified
CNA Cisco Cisco IOS XE Software affected 16.7.3 Not specified
CNA Cisco Cisco IOS XE Software affected 16.6.7 Not specified
CNA Cisco Cisco IOS XE Software affected 16.9.6 Not specified
CNA Cisco Cisco IOS XE Software affected 16.9.2 Not specified
CNA Cisco Cisco IOS XE Software affected 3.16.10S Not specified
CNA Cisco Cisco IOS XE Software affected 16.10.1 Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.1t Not specified
CNA Cisco Cisco IOS XE Software affected 3.18.3bSP Not specified
CNA Cisco Cisco IOS XE Software affected 3.13.9S Not specified
CNA Cisco Cisco IOS XE Software affected 3.18.3aSP Not specified
CNA Cisco Cisco IOS XE Software affected 3.18.5SP Not specified
CNA Cisco Cisco IOS XE Software affected 16.9.1 Not specified
CNA Cisco Cisco IOS XE Software affected 16.8.1a Not specified
CNA Cisco Cisco IOS XE Software affected 3.18.8aSP Not specified
CNA Cisco Cisco IOS XE Software affected 16.9.3s Not specified
CNA Cisco Cisco IOS XE Software affected 16.6.7a Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.2 Not specified
CNA Cisco Cisco IOS XE Software affected 16.11.1 Not specified
CNA Cisco Cisco IOS XE Software affected 16.9.3 Not specified
CNA Cisco Cisco IOS XE Software affected 16.11.1s Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.1 Not specified
CNA Cisco Cisco IOS XE Software affected 3.16.9S Not specified
CNA Cisco Cisco IOS XE Software affected 17.1.1 Not specified
CNA Cisco Cisco IOS XE Software affected 17.1.2 Not specified
CNA Cisco Cisco IOS XE Software affected 16.10.1d Not specified
CNA Cisco Cisco IOS XE Software affected 17.1.1t Not specified
CNA Cisco Cisco IOS XE Software affected 16.9.4 Not specified
CNA Cisco Cisco IOS XE Software affected 16.8.3 Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.2t Not specified
CNA Cisco Cisco IOS XE Software affected 16.9.5 Not specified
CNA Cisco Cisco IOS XE Software affected 3.16.7S Not specified
CNA Cisco Cisco IOS XE Software affected 16.8.1s Not specified
CNA Cisco Cisco IOS XE Software affected 16.10.1e Not specified
CNA Cisco Cisco IOS XE Software affected 16.8.2 Not specified
CNA Cisco Cisco IOS XE Software affected 16.6.4 Not specified
CNA Cisco Cisco IOS XE Software affected 16.8.1b Not specified
CNA Cisco Cisco IOS XE Software affected 16.10.1a Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.1z Not specified
CNA Cisco Cisco IOS XE Software affected 16.8.1c Not specified
CNA Cisco Cisco IOS XE Software affected 16.9.1a Not specified
CNA Cisco Cisco IOS XE Software affected 3.16.7aS Not specified
CNA Cisco Cisco IOS XE Software affected 16.9.5f Not specified
CNA Cisco Cisco IOS XE Software affected 16.6.4a Not specified
CNA Cisco Cisco IOS XE Software affected 16.10.1g Not specified
CNA Cisco Cisco IOS XE Software affected 3.13.10S Not specified
CNA Cisco Cisco IOS XE Software affected 16.8.1 Not specified
CNA Cisco Cisco IOS XE Software affected 16.6.6 Not specified
CNA Cisco Cisco IOS XE Software affected 16.9.2a Not specified
CNA Cisco Cisco IOS XE Software affected 16.8.1d Not specified
CNA Cisco Cisco IOS XE Software affected 16.10.3 Not specified
CNA Cisco Cisco IOS XE Software affected 3.18.4SP Not specified
CNA Cisco Cisco IOS XE Software affected 3.18.6SP Not specified
CNA Cisco Cisco IOS XE Software affected 3.18.3SP Not specified
CNA Cisco Cisco IOS XE Software affected 16.7.1a Not specified
CNA Cisco Cisco IOS XE Software affected 16.11.1c Not specified
CNA Cisco Cisco IOS XE Software affected 16.10.1s Not specified
CNA Cisco Cisco IOS XE Software affected 17.2.1r Not specified
CNA Cisco Cisco IOS XE Software affected 3.16.7bS Not specified
CNA Cisco Cisco IOS XE Software affected 17.1.1a Not specified
CNA Cisco Cisco IOS XE Software affected 16.10.2 Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.2a Not specified
CNA Cisco Cisco IOS XE Software affected 3.16.6bS Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.1c Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.1s Not specified
CNA Cisco Cisco IOS XE Software affected 16.7.4 Not specified
CNA Cisco Cisco IOS XE Software affected 3.18.9SP Not specified
CNA Cisco Cisco IOS XE Software affected 17.2.2 Not specified
CNA Cisco Cisco IOS XE Software affected 16.9.8 Not specified
CNA Cisco Cisco IOS XE Software affected 16.9.7 Not specified
CNA Cisco Cisco IOS XE Software affected 17.1.3 Not specified
CNA Cisco Cisco IOS XE Software affected 17.3.1a Not specified
CNA Cisco Cisco IOS XE Software affected 17.3.2a Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.5 Not specified
CNA Cisco Cisco IOS XE Software affected 17.3.1w Not specified
CNA Cisco Cisco IOS XE Software affected 17.3.2 Not specified
CNA Cisco Cisco IOS XE Software affected 17.4.1 Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.4a Not specified
CNA Cisco Cisco IOS XE Software affected 17.4.1a Not specified
CNA Cisco Cisco IOS XE Software affected 3.16.10bS Not specified
CNA Cisco Cisco IOS XE Software affected 17.3.1x Not specified
CNA Cisco Cisco IOS XE Software affected 17.3.3 Not specified
CNA Cisco Cisco IOS XE Software affected 16.6.9 Not specified
CNA Cisco Cisco IOS XE Software affected 17.2.3 Not specified
CNA Cisco Cisco IOS XE Software affected 17.5.1 Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.1z1 Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.5a Not specified
CNA Cisco Cisco IOS XE Software affected 17.4.1b Not specified
CNA Cisco Cisco IOS XE Software affected 17.3.1z Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.5b Not specified
CNA Cisco Cisco IOS XE Software affected 17.4.2 Not specified
CNA Cisco Cisco IOS XE Software affected 17.3.3a Not specified
CNA Cisco Cisco IOS XE Software affected 17.3.5 Not specified
CNA Cisco Cisco IOS XE Software affected 17.3.4 Not specified
CNA Cisco Cisco IOS XE Software affected 17.5.1a Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.6 Not specified
CNA Cisco Cisco IOS XE Software affected 17.6.1 Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.1z2 Not specified
CNA Cisco Cisco IOS XE Software affected 16.6.10 Not specified
CNA Cisco Cisco IOS XE Software affected 17.3.4a Not specified
CNA Cisco Cisco IOS XE Software affected 17.6.1a Not specified
CNA Cisco Cisco IOS XE Software affected 17.7.1 Not specified
CNA Cisco Cisco IOS XE Software affected 17.6.1x Not specified
CNA Cisco Cisco IOS XE Software affected 17.6.2 Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.6a Not specified
CNA Cisco Cisco IOS XE Software affected 17.3.4c Not specified
CNA Cisco Cisco IOS XE Software affected 17.4.2a Not specified
CNA Cisco Cisco IOS XE Software affected 17.3.4b Not specified
CNA Cisco Cisco IOS XE Software affected 17.7.1a Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.7 Not specified
CNA Cisco Cisco IOS XE Software affected 17.8.1a Not specified
CNA Cisco Cisco IOS XE Software affected 17.6.3a Not specified
CNA Cisco Cisco IOS XE Software affected 17.6.3 Not specified
CNA Cisco Cisco IOS XE Software affected 17.7.2 Not specified
CNA Cisco Cisco IOS XE Software affected 17.7.1b Not specified
CNA Cisco Cisco IOS XE Software affected 17.9.1w Not specified
CNA Cisco Cisco IOS XE Software affected 17.3.5a Not specified
CNA Cisco Cisco IOS XE Software affected 17.6.1z Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.8 Not specified
CNA Cisco Cisco IOS XE Software affected 17.8.1 Not specified
CNA Cisco Cisco IOS XE Software affected 17.9.1 Not specified
CNA Cisco Cisco IOS XE Software affected 17.6.4 Not specified
CNA Cisco Cisco IOS XE Software affected 17.3.5b Not specified
CNA Cisco Cisco IOS XE Software affected 17.9.1a Not specified
CNA Cisco Cisco IOS XE Software affected 17.3.6 Not specified
CNA Cisco Cisco IOS XE Software affected 17.10.1 Not specified
CNA Cisco Cisco IOS XE Software affected 16.9.8a Not specified
CNA Cisco Cisco IOS XE Software affected 17.6.1z1 Not specified
CNA Cisco Cisco IOS XE Software affected 17.10.1a Not specified
CNA Cisco Cisco IOS XE Software affected 17.9.2 Not specified
CNA Cisco Cisco IOS XE Software affected 17.6.5 Not specified
CNA Cisco Cisco IOS XE Software affected 17.9.1x Not specified
CNA Cisco Cisco IOS XE Software affected 17.9.1y Not specified
CNA Cisco Cisco IOS XE Software affected 16.9.8b Not specified
CNA Cisco Cisco IOS XE Software affected 17.3.7 Not specified
CNA Cisco Cisco IOS XE Software affected 17.9.2a Not specified
CNA Cisco Cisco IOS XE Software affected 17.9.3 Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.9 Not specified
CNA Cisco Cisco IOS XE Software affected 17.11.1 Not specified
CNA Cisco Cisco IOS XE Software affected 17.10.1b Not specified
CNA Cisco Cisco IOS XE Software affected 17.6.6 Not specified
CNA Cisco Cisco IOS XE Software affected 17.9.1x1 Not specified
CNA Cisco Cisco IOS XE Software affected 17.11.1a Not specified
CNA Cisco Cisco IOS XE Software affected 17.9.3a Not specified
CNA Cisco Cisco IOS XE Software affected 17.12.1 Not specified
CNA Cisco Cisco IOS XE Software affected 17.3.8 Not specified
CNA Cisco Cisco IOS XE Software affected 17.9.4 Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.10 Not specified
CNA Cisco Cisco IOS XE Software affected 17.12.1w Not specified
CNA Cisco Cisco IOS XE Software affected 17.9.1y1 Not specified
CNA Cisco Cisco IOS XE Software affected 17.12.1a Not specified
CNA Cisco Cisco IOS XE Software affected 17.9.5 Not specified
CNA Cisco Cisco IOS XE Software affected 17.13.1 Not specified
CNA Cisco Cisco IOS XE Software affected 17.12.1x Not specified
CNA Cisco Cisco IOS XE Software affected 17.12.2 Not specified
CNA Cisco Cisco IOS XE Software affected 17.14.1 Not specified
CNA Cisco Cisco IOS XE Software affected 17.9.4a Not specified
CNA Cisco Cisco IOS XE Software affected 17.3.8a Not specified
CNA Cisco Cisco IOS XE Software affected 17.6.6a Not specified
CNA Cisco Cisco IOS XE Software affected 17.6.5a Not specified
CNA Cisco Cisco IOS XE Software affected 17.6.7 Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.10a Not specified
CNA Cisco Cisco IOS XE Software affected 17.15.1 Not specified
CNA Cisco Cisco IOS XE Software affected 17.13.1a Not specified
CNA Cisco Cisco IOS XE Software affected 17.12.2a Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.11 Not specified
CNA Cisco Cisco IOS XE Software affected 17.12.3 Not specified
CNA Cisco Cisco IOS XE Software affected 17.12.1y Not specified
CNA Cisco Cisco IOS XE Software affected 17.12.1z Not specified
CNA Cisco Cisco IOS XE Software affected 17.9.5a Not specified
CNA Cisco Cisco IOS XE Software affected 17.14.1a Not specified
CNA Cisco Cisco IOS XE Software affected 17.9.5b Not specified
CNA Cisco Cisco IOS XE Software affected 17.6.8 Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.12 Not specified
CNA Cisco Cisco IOS XE Software affected 17.12.4 Not specified
CNA Cisco Cisco IOS XE Software affected 17.9.6 Not specified
CNA Cisco Cisco IOS XE Software affected 17.17.1 Not specified
CNA Cisco Cisco IOS XE Software affected 17.16.1 Not specified
CNA Cisco Cisco IOS XE Software affected 17.15.1w Not specified
CNA Cisco Cisco IOS XE Software affected 17.12.3a Not specified
CNA Cisco Cisco IOS XE Software affected 17.9.5c Not specified
CNA Cisco Cisco IOS XE Software affected 17.15.1a Not specified
CNA Cisco Cisco IOS XE Software affected 17.12.1z1 Not specified
CNA Cisco Cisco IOS XE Software affected 17.15.2 Not specified
CNA Cisco Cisco IOS XE Software affected 17.15.1b Not specified
CNA Cisco Cisco IOS XE Software affected 17.9.5d Not specified
CNA Cisco Cisco IOS XE Software affected 17.15.1x Not specified
CNA Cisco Cisco IOS XE Software affected 17.9.6a Not specified
CNA Cisco Cisco IOS XE Software affected 17.12.1z2 Not specified
CNA Cisco Cisco IOS XE Software affected 17.6.8a Not specified
CNA Cisco Cisco IOS XE Software affected 17.16.1a Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.13 Not specified
CNA Cisco Cisco IOS XE Software affected 17.15.3 Not specified
CNA Cisco Cisco IOS XE Software affected 17.9.7 Not specified
CNA Cisco Cisco IOS XE Software affected 17.12.5 Not specified
CNA Cisco Cisco IOS XE Software affected 17.15.1y Not specified
CNA Cisco Cisco IOS XE Software affected 17.9.5e Not specified
CNA Cisco Cisco IOS XE Software affected 17.12.4a Not specified
CNA Cisco Cisco IOS XE Software affected 17.15.2a Not specified
CNA Cisco Cisco IOS XE Software affected 17.15.2c Not specified
CNA Cisco Cisco IOS XE Software affected 17.15.2b Not specified
CNA Cisco Cisco IOS XE Software affected 17.12.1z3 Not specified
CNA Cisco Cisco IOS XE Software affected 17.9.5f Not specified
CNA Cisco Cisco IOS XE Software affected 17.12.4b Not specified
CNA Cisco Cisco IOS XE Software affected 17.12.5a Not specified
CNA Cisco Cisco IOS XE Software affected 17.18.1 Not specified
CNA Cisco Cisco IOS XE Software affected 17.12.6 Not specified
CNA Cisco Cisco IOS XE Software affected 17.12.1z4 Not specified
CNA Cisco Cisco IOS XE Software affected 17.9.8 Not specified
CNA Cisco Cisco IOS XE Software affected 17.9.7a Not specified
CNA Cisco Cisco IOS XE Software affected 17.15.3a Not specified
CNA Cisco Cisco IOS XE Software affected 17.15.4 Not specified
CNA Cisco Cisco IOS XE Software affected 17.12.5b Not specified
CNA Cisco Cisco IOS XE Software affected 17.15.3b Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.14 Not specified
CNA Cisco Cisco IOS XE Software affected 17.9.7b Not specified
CNA Cisco Cisco IOS XE Software affected 17.12.5c Not specified
CNA Cisco Cisco IOS XE Software affected 17.18.1a Not specified
CNA Cisco Cisco IOS XE Software affected 17.15.4a Not specified
CNA Cisco Cisco IOS XE Software affected 17.18.2 Not specified
CNA Cisco Cisco IOS XE Software affected 17.18.1w Not specified
CNA Cisco Cisco IOS XE Software affected 17.15.4b Not specified
CNA Cisco Cisco IOS XE Software affected 17.12.6a Not specified
CNA Cisco Cisco IOS XE Software affected 17.15.4c Not specified
CNA Cisco Cisco IOS XE Software affected 17.9.9 Not specified
CNA Cisco Cisco IOS XE Software affected 17.12.5d Not specified
CNA Cisco Cisco IOS XE Software affected 16.12.15 Not specified
CNA Cisco Cisco IOS XE Software affected 17.15.4s1 Not specified
CNA Cisco Cisco IOS XE Software affected 17.12.1z5 Not specified
CNA Cisco Cisco IOS XE Software affected 17.18.1x Not specified
CNA Cisco Cisco IOS XE Software affected 17.12.1z6 Not specified
CNA Cisco Cisco IOS XE Software affected 17.15.4d Not specified
CNA Cisco Cisco IOS XE Software affected 17.12.6b Not specified
CNA Cisco Cisco IOS XE Software affected 17.4.1c Not specified
CNA Cisco Cisco IOS XE Software affected 17.18.1y Not specified

References

ReferenceSourceLinkTags
sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxe-... [email protected] sec.cloudapps.cisco.com
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Additional Advisory Data

Exploits

CNA: The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory.

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