# CVE-2026-20269: Cisco IOS XE improper resource lifetime control

Source: https://junglewise.ai/threats/cve-2026-20269-cisco-ios-xe-improper-resource-lifetime-control  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-05. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-20269 · Severity: high · CVSS 8.6 · Published 2026-08-05

Cisco IOS XE is the operating system running on Cisco network switches and routers used to manage enterprise networks. This vulnerability involves improper handling of system resources (memory and file handlers) during their lifecycle, which could allow an attacker to cause service disruptions or potentially execute code remotely. Cisco has released patched software versions to address this issue, with no known active exploitation at this time.

Technologies: [Cisco IOS XE](https://junglewise.ai/threats/technologies/ios-xe). Vendors: [Cisco](https://junglewise.ai/threats/vendors/cisco).

## Quick answers

**Is CVE-2026-20269 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-20269 being exploited in the wild.

**How severe is CVE-2026-20269?** High severity, with a CVSS score of 8.6, published 5 August 2026.

**Which products and versions are affected?** Cisco IOS XE 17.9 before 17.9.10, 17.12 before 17.12.8, 17.15 before 17.15.6, 17.18 before 17.18.4, 26.1 before 26.1.2.

**Is there a fix for CVE-2026-20269?** A patch was published on 2026-08-05: Fixed releases available: 17.9.10, 17.12.8, 17.15.6, 17.18.4/4a, 26.1.2 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-20269 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-20269?** Check whether you run Cisco IOS XE at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

CVE-2026-20269 is one of seven vulnerabilities in a Cisco software hardening release addressing improper resource lifetime control issues grouped under CWE-664. This class of weakness includes memory and file handler management, null pointer dereferences, and invalid free operations. The vulnerability affects Cisco IOS XE Software running in autonomous or controller mode across multiple product lines (excluding Catalyst 3650 and 3850 Series). Attack vector is network-based with no authentication or user interaction required (CVSS 8.6). Cisco has released fixed versions for affected release trains (17.9.10, 17.12.8, 17.15.6, 17.18.4/4a, 26.1.2) and indicates no workarounds are available.

## Affected products

- Cisco IOS XE 17.9 before 17.9.10, 17.12 before 17.12.8, 17.15 before 17.15.6, 17.18 before 17.18.4, 26.1 before 26.1.2

## Timeline

- 2026-08-05: disclosed: CVE-2026-20269 published by Cisco
- 2026-08-05: patched: Fixed releases available: 17.9.10, 17.12.8, 17.15.6, 17.18.4/4a, 26.1.2

## References

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

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