← Vulnerability feed

Vulnerability record · CVE-2026-20268 · published 5 August 2026

CVE-2026-20268: Cisco ios xe memory buffer overflow vulnerability

Cisco · Ios Xe

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco IOS XE Software engineering team has conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-20268 are related to issues with improper restriction of operations within the bounds of a memory buffer that are grouped under the Common Weakness Enumeration (CWE) Pillar CWE-119.

8.6 CVSS 3.1 High EPSS 0.47% · top 62.1% CWE-119 · Memory buffer overflow
8.6CVSS 3.1 base score
0.47%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
2References
14 Aug 2026Last modified by NVD

Description

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco IOS XE Software engineering team has conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-20268 are related to issues with improper restriction of operations within the bounds of a memory buffer that are grouped under the Common Weakness Enumeration (CWE) Pillar CWE-119.

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

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-hardening-iosxe-V8NMuMZJ Vendor Advisory
https://www.cve.org/Media/News/item/blog/2026/06/16/Preserving-Vulnerability-Level-Identification

Track CVE-2026-20268 inside VULONE

Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.

Start free Open in platform

Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

10.0CVE-2023-20198Cisco IOS XE Web UI unauthenticated privilege escalation and implant deploymentCVE-2023-20198 is a critical flaw in the Cisco IOS XE web UI that lets an unauthenticated remote attacker gain initial access and create a local priv…KEVEPSS 100%analysed9.8CVE-2018-0151Cisco IOS/IOS XE QoS UDP Port 18999 Buffer OverflowCisco IOS and IOS XE contain a buffer overflow in the QoS subsystem caused by incorrect bounds checking of values in packets sent to UDP port 18999. …KEVEPSS 14%analysed9.8CVE-2017-3881Cisco IOS/IOS XE CMP Telnet Option Handling RCECisco IOS and IOS XE fail to restrict CMP-specific Telnet options to internal cluster communications and mishandle malformed CMP Telnet options, so a…KEVEPSS 99%analysed8.8CVE-2018-0167Cisco IOS, IOS XE and IOS XR LLDP buffer overflowMultiple buffer overflow flaws exist in the Link Layer Discovery Protocol (LLDP) subsystem of Cisco IOS, IOS XE and IOS XR Software. An unauthenticat…KEVEPSS 3.4%analysed8.8CVE-2017-6736Cisco IOS and IOS XE SNMP buffer overflow remote code executionThe SNMP subsystem in Cisco IOS and IOS XE contains a buffer overflow that can be triggered by a crafted SNMP packet sent over IPv4 or IPv6. It affec…KEVEPSS 70%analysed8.8CVE-2017-6737Cisco IOS and IOS XE SNMP Buffer Overflow RCECisco IOS and IOS XE contain a buffer overflow in the SNMP implementation that affects SNMPv1, v2c, and v3. An authenticated remote attacker who know…KEVEPSS 45%analysed8.8CVE-2017-6738Cisco IOS and IOS XE SNMP buffer overflow allows remote code executionThe SNMP subsystem in Cisco IOS and IOS XE Software contains a buffer overflow that affects SNMP versions 1, 2c, and 3. An authenticated remote attac…KEVEPSS 11%analysed8.8CVE-2017-6739Cisco IOS and IOS XE SNMP buffer overflow allows remote code executionCisco IOS and IOS XE contain a buffer overflow in the SNMP implementation that affects SNMP versions 1, 2c, and 3. A remote attacker who knows the SN…KEVEPSS 11%analysed

Source: NIST National Vulnerability Database (record CVE-2026-20268), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.