Is CVE-2026-20268 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-20268 being exploited in the wild.

How severe is CVE-2026-20268?

High severity, with a CVSS score of 8.6, published 5 August 2026.

Which products and versions are affected?

Cisco IOS XE 17.9, 17.12, 17.15, 17.18, 26.1.

Is there a fix for CVE-2026-20268?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-20268 attacked?

It is attacked over the network, in an operating system.

Am I affected by CVE-2026-20268?

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.

CVE-2026-20268: Cisco IOS XE Software buffer overflow in memory operations

CVE-2026-20268 · Severity: high · CVSS 8.6 · Published 2026-08-05

Cisco IOS XE Software, used in enterprise network switches and routers, contains multiple memory buffer handling vulnerabilities discovered during internal security review. An attacker with network access could exploit these flaws to crash devices or potentially execute unauthorized code, disrupting network operations and compromising data integrity.

Technologies: Cisco IOS XE. Vendors: Cisco.

Quick answers

Is CVE-2026-20268 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-20268 being exploited in the wild.
How severe is CVE-2026-20268?: High severity, with a CVSS score of 8.6, published 5 August 2026.
Which products and versions are affected?: Cisco IOS XE 17.9, 17.12, 17.15, 17.18, 26.1.
Is there a fix for CVE-2026-20268?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-20268 attacked?: It is attacked over the network, in an operating system.
Am I affected by CVE-2026-20268?: 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-2026-20268 covers improper restriction of operations within memory buffer bounds (CWE-119), including buffer overflows and out-of-bounds writes. The vulnerability affects Cisco IOS XE Software running in autonomous or controller mode on various network devices. The issue is remotely exploitable over the network without authentication or user interaction required. A successful exploit could allow an attacker to achieve high impact on confidentiality, integrity, and availability. Cisco has released fixed software versions for affected releases (17.9.10, 17.12.8, 17.15.6, 17.18.4/4a, 26.1.2). No workarounds are available.

Affected products

Cisco IOS XE 17.9, 17.12, 17.15, 17.18, 26.1

Timeline

2026-08-05: disclosed: Advisory published by Cisco PSIRT

References

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