# CVE-2017-12232: Cisco IOS Software for Cisco Integrated Services Routers Denial-of-Service Vulnerability

Source: https://junglewise.ai/threats/cve-2017-12232-cisco-ios-software-for-cisco-integrated-services-routers-denial  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2022-03-03. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-2017-12232 · Severity: critical · CVSS 6.5 · Exploited in the wild · Published 2022-03-03

A vulnerability in Cisco IOS Software for Integrated Services Routers Generation 2 (ISR G2) allows an unauthenticated, adjacent attacker to cause a denial of service (DoS) by sending crafted Ethernet frames. The issue stems from a misclassification of Ethernet frames, which causes the affected device to reload.

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

## Quick answers

**Is CVE-2017-12232 exploited in the wild?** Yes. CVE-2017-12232 is known to be exploited in the wild, first recorded on 3 March 2022. Treat it as urgent.

**How severe is CVE-2017-12232?** Critical severity, with a CVSS score of 6.5, published 3 March 2022.

**Which products and versions are affected?** Cisco IOS 15.0 through 15.6; Cisco Integrated Services Routers Generation 2 (ISR G2) Routers.

**Is there a fix for CVE-2017-12232?** 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-2017-12232 attacked?** It is attacked from the adjacent network, in device firmware.

**Am I affected by CVE-2017-12232?** Check whether you run Cisco IOS, Cisco Ios Software or Cisco IOS XE. 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.

## Affected products

- Cisco IOS 15.0 through 15.6
- Cisco Integrated Services Routers Generation 2 (ISR G2) Routers

## Timeline

- 2017-09-27: disclosed: Original Cisco advisory date (from reference URL)
- 2022-03-03: kev added: Added to CISA Known Exploited Vulnerabilities Catalog

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